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313822 | https://en.wikipedia.org/wiki/Haddock | Haddock | The haddock (Melanogrammus aeglefinus) is a saltwater ray-finned fish from the family Gadidae, the true cods. It is the only species in the monotypic genus Melanogrammus. It is found in the North Atlantic Ocean and associated seas, where it is an important species for fisheries, especially in northern Europe, where it ... | Biology and health sciences | Acanthomorpha | null |
313830 | https://en.wikipedia.org/wiki/Bulldozer | Bulldozer | A bulldozer or dozer (also called a crawler) is a large, motorized machine equipped with a metal blade to the front for pushing material: soil, sand, snow, rubble, or rock during construction work. It travels most commonly on continuous tracks, though specialized models riding on large off-road tires are also produced... | Technology | Specific-purpose transportation | null |
313833 | https://en.wikipedia.org/wiki/Swiss%20Army%20knife | Swiss Army knife | The Swiss Army knife (SAK; ) is a pocketknife, generally multi-tooled, now manufactured by Victorinox. The term "Swiss Army knife" was coined by American soldiers after World War II because they had trouble pronouncing the German word "", meaning "officer’s knife".
The Swiss Army knife generally has a drop-point main ... | Technology | Knives | null |
313925 | https://en.wikipedia.org/wiki/Ichthyostega | Ichthyostega | Ichthyostega (from , 'fish' and , 'roof') is an extinct genus of limbed tetrapodomorphs from the Late Devonian of what is now Greenland. It was among the earliest four-limbed vertebrates ever in the fossil record and was one of the first with weight-bearing adaptations for terrestrial locomotion. Ichthyostega possess... | Biology and health sciences | Prehistoric amphibians | Animals |
314101 | https://en.wikipedia.org/wiki/Ichthyosauria | Ichthyosauria | Ichthyosauria is an order of large extinct marine reptiles sometimes referred to as "ichthyosaurs", although the term is also used for wider clades in which the order resides.
Ichthyosaurians thrived during much of the Mesozoic era; based on fossil evidence, they first appeared around 250 million years ago (Ma) and at... | Biology and health sciences | Prehistoric marine reptiles | Animals |
4053383 | https://en.wikipedia.org/wiki/Skeleton%20key | Skeleton key | A skeleton key (also known as a passkey) is a type of master key in which the serrated edge has been removed in such a way that it can open numerous locks, most commonly the warded lock. The term derives from the fact that the key has been reduced to its essential parts.
Master keys
A skeleton key is a key that has b... | Technology | Mechanisms | null |
4055928 | https://en.wikipedia.org/wiki/Structure%20%28mathematical%20logic%29 | Structure (mathematical logic) | In universal algebra and in model theory, a structure consists of a set along with a collection of finitary operations and relations that are defined on it.
Universal algebra studies structures that generalize the algebraic structures such as groups, rings, fields and vector spaces. The term universal algebra is used ... | Mathematics | Model theory | null |
4056309 | https://en.wikipedia.org/wiki/Banded%20bullfrog | Banded bullfrog | The banded bullfrog (Kaloula pulchra) is a species of frog in the narrow-mouthed frog family Microhylidae. Native to Southeast Asia, it is also known as the Asian painted frog, digging frog, Malaysian bullfrog, common Asian frog, and painted balloon frog. In the pet trade, it is sometimes called the chubby frog. Adults... | Biology and health sciences | Frogs and toads | Animals |
4058774 | https://en.wikipedia.org/wiki/Human%20reproduction | Human reproduction | Human sexual reproduction, to produce offspring, begins with fertilization. Successful reproduction typically involves sexual intercourse between a healthy, sexually mature and fertile male and female. During sexual intercourse, sperm cells are ejaculated into the vagina through the penis, resulting in fertilization of... | Biology and health sciences | Human reproduction | Biology |
4059023 | https://en.wikipedia.org/wiki/Search%20engine | Search engine | A search engine is a software system that provides hyperlinks to web pages and other relevant information on the Web in response to a user's query. The user inputs a query within a web browser or a mobile app, and the search results are often a list of hyperlinks, accompanied by textual summaries and images. Users also... | Technology | Internet | null |
14341914 | https://en.wikipedia.org/wiki/Jaekelopterus | Jaekelopterus | Jaekelopterus is a genus of predatory eurypterid, a group of extinct aquatic arthropods. Fossils of Jaekelopterus have been discovered in deposits of Early Devonian age, from the Pragian and Emsian stages. There are two known species: the type species J. rhenaniae from brackish to fresh water strata in the Rhineland, a... | Biology and health sciences | Fossil arthropods | Animals |
41244 | https://en.wikipedia.org/wiki/Hybrid%20%28biology%29 | Hybrid (biology) | In biology, a hybrid is the offspring resulting from combining the qualities of two organisms of different varieties, subspecies, species or genera through sexual reproduction. Generally, it means that each cell has genetic material from two different organisms, whereas an individual where some cells are derived from a... | Biology and health sciences | Genetics and taxonomy | null |
41316 | https://en.wikipedia.org/wiki/Linear%20polarization | Linear polarization | In electrodynamics, linear polarization or plane polarization of electromagnetic radiation is a confinement of the electric field vector or magnetic field vector to a given plane along the direction of propagation. The term linear polarization (French: polarisation rectiligne) was coined by Augustin-Jean Fresnel in 182... | Physical sciences | Optics | Physics |
41389 | https://en.wikipedia.org/wiki/Multiplexing | Multiplexing | In telecommunications and computer networking, multiplexing (sometimes contracted to muxing) is a method by which multiple analog or digital signals are combined into one signal over a shared medium. The aim is to share a scarce resource a physical transmission medium. For example, in telecommunications, several telep... | Technology | Signal processing | null |
41402 | https://en.wikipedia.org/wiki/Neper | Neper | The neper (symbol: Np) is a logarithmic unit for ratios of measurements of physical field and power quantities, such as gain and loss of electronic signals. The unit's name is derived from the name of John Napier, the inventor of logarithms. As is the case for the decibel and bel, the neper is a unit defined in the int... | Physical sciences | Ratio | Basics and measurement |
41413 | https://en.wikipedia.org/wiki/Network%20topology | Network topology | Network topology is the arrangement of the elements (links, nodes, etc.) of a communication network. Network topology can be used to define or describe the arrangement of various types of telecommunication networks, including command and control radio networks, industrial fieldbusses and computer networks.
Network top... | Technology | Networks | null |
41415 | https://en.wikipedia.org/wiki/Noise | Noise | Noise is sound, chiefly unwanted, unintentional, or harmful sound considered unpleasant, loud, or disruptive to mental or hearing faculties. From a physics standpoint, there is no distinction between noise and desired sound, as both are vibrations through a medium, such as air or water. The difference arises when the b... | Physical sciences | Waves | null |
41458 | https://en.wikipedia.org/wiki/Optical%20disc | Optical disc | An optical disc is a flat, usually disc-shaped object that stores information in the form of physical variations on its surface that can be read with the aid of a beam of light. Optical discs can be reflective, where the light source and detector are on the same side of the disc, or transmissive, where light shines th... | Technology | Data storage | null |
41460 | https://en.wikipedia.org/wiki/Optical%20isolator | Optical isolator | An optical isolator, or optical diode, is an optical component which allows the transmission of light in only one direction. It is typically used to prevent unwanted feedback into an optical oscillator, such as a laser cavity.
The operation of conventional optical isolators relies on the Faraday effect (which in turn ... | Technology | Optical components | null |
41461 | https://en.wikipedia.org/wiki/Optical%20path%20length | Optical path length | In optics, optical path length (OPL, denoted Λ in equations), also known as optical length or optical distance, is the length that light needs to travel through a vacuum to create the same phase difference as it would have when traveling through a given medium. It is calculated by taking the product of the geometric le... | Physical sciences | Optics | Physics |
41464 | https://en.wikipedia.org/wiki/Visible%20spectrum | Visible spectrum | The visible spectrum is the band of the electromagnetic spectrum that is visible to the human eye. Electromagnetic radiation in this range of wavelengths is called visible light (or simply light).
The optical spectrum is sometimes considered to be the same as the visible spectrum, but some authors define the term more ... | Physical sciences | Electrodynamics | null |
41515 | https://en.wikipedia.org/wiki/Cod | Cod | Cod (: cod) is the common name for the demersal fish genus Gadus, belonging to the family Gadidae. Cod is also used as part of the common name for a number of other fish species, and one species that belongs to genus Gadus is commonly not called cod (Alaska pollock, Gadus chalcogrammus).
The two most common species of... | Biology and health sciences | Acanthomorpha | null |
41519 | https://en.wikipedia.org/wiki/Photic%20zone | Photic zone | The photic zone (or euphotic zone, epipelagic zone, or sunlight zone) is the uppermost layer of a body of water that receives sunlight, allowing phytoplankton to perform photosynthesis. It undergoes a series of physical, chemical, and biological processes that supply nutrients into the upper water column. The photic zo... | Physical sciences | Oceanography | Earth science |
41545 | https://en.wikipedia.org/wiki/Avogadro%20constant | Avogadro constant | The Avogadro constant, commonly denoted or , is an SI defining constant with an exact value of (reciprocal moles). It is this defined number of constituent particles (usually molecules, atoms, ions, or ion pairs—in general, entities) per mole (SI unit) and used as a normalization factor in relating the amount of subs... | Physical sciences | Substance | Chemistry |
41559 | https://en.wikipedia.org/wiki/Plane%20wave | Plane wave | In physics, a plane wave is a special case of a wave or field: a physical quantity whose value, at any given moment, is constant through any plane that is perpendicular to a fixed direction in space.
For any position in space and any time , the value of such a field can be written as
where is a unit-length vector, ... | Physical sciences | Waves | Physics |
41564 | https://en.wikipedia.org/wiki/Polarization%20%28waves%29 | Polarization (waves) | (also ) is a property of transverse waves which specifies the geometrical orientation of the oscillations. In a transverse wave, the direction of the oscillation is perpendicular to the direction of motion of the wave. One example of a polarized transverse wave is vibrations traveling along a taut string (see image),... | Physical sciences | Optics | null |
41600 | https://en.wikipedia.org/wiki/Pulse | Pulse | In medicine, the pulse is the rhythmic throbbing of each artery in response to the cardiac cycle (heartbeat). The pulse may be palpated in any place that allows an artery to be compressed near the surface of the body, such as at the neck (carotid artery), wrist (radial artery or ulnar artery), at the groin (femoral art... | Biology and health sciences | Medical procedures | null |
41625 | https://en.wikipedia.org/wiki/Radiometry | Radiometry | Radiometry is a set of techniques for measuring electromagnetic radiation, including visible light. Radiometric techniques in optics characterize the distribution of the radiation's power in space, as opposed to photometric techniques, which characterize the light's interaction with the human eye. The fundamental diffe... | Physical sciences | Electromagnetic radiation | Physics |
41638 | https://en.wikipedia.org/wiki/Cycloid | Cycloid | In geometry, a cycloid is the curve traced by a point on a circle as it rolls along a straight line without slipping. A cycloid is a specific form of trochoid and is an example of a roulette, a curve generated by a curve rolling on another curve.
The cycloid, with the cusps pointing upward, is the curve of fastest des... | Mathematics | Two-dimensional space | null |
41641 | https://en.wikipedia.org/wiki/Reflection%20coefficient | Reflection coefficient | In physics and electrical engineering the reflection coefficient is a parameter that describes how much of a wave is reflected by an impedance discontinuity in the transmission medium. It is equal to the ratio of the amplitude of the reflected wave to the incident wave, with each expressed as phasors. For example, it... | Physical sciences | Optics | Physics |
41660 | https://en.wikipedia.org/wiki/Resonance | Resonance | Resonance is a phenomenon that occurs when an object or system is subjected to an external force or vibration that matches its natural frequency. When this happens, the object or system absorbs energy from the external force and starts vibrating with a larger amplitude. Resonance can occur in various systems, such as m... | Physical sciences | Waves | null |
41698 | https://en.wikipedia.org/wiki/Shield | Shield | A shield is a piece of personal armour held in the hand, which may or may not be strapped to the wrist or forearm. Shields are used to intercept specific attacks, whether from close-ranged weaponry like spears or long ranged projectiles such as arrows. They function as means of active blocks, as well as to provide pass... | Technology | Armour | null |
41706 | https://en.wikipedia.org/wiki/Signal-to-noise%20ratio | Signal-to-noise ratio | Signal-to-noise ratio (SNR or S/N) is a measure used in science and engineering that compares the level of a desired signal to the level of background noise. SNR is defined as the ratio of signal power to noise power, often expressed in decibels. A ratio higher than 1:1 (greater than 0 dB) indicates more signal than no... | Technology | Basics_4 | null |
41741 | https://en.wikipedia.org/wiki/Standing%20wave | Standing wave | In physics, a standing wave, also known as a stationary wave, is a wave that oscillates in time but whose peak amplitude profile does not move in space. The peak amplitude of the wave oscillations at any point in space is constant with respect to time, and the oscillations at different points throughout the wave are i... | Physical sciences | Waves | Physics |
41789 | https://en.wikipedia.org/wiki/Thermodynamic%20temperature | Thermodynamic temperature | Thermodynamic temperature is a quantity defined in thermodynamics as distinct from kinetic theory or statistical mechanics.
Historically, thermodynamic temperature was defined by Lord Kelvin in terms of a macroscopic relation between thermodynamic work and heat transfer as defined in thermodynamics, but the kelvin was... | Physical sciences | Thermodynamics | Physics |
41799 | https://en.wikipedia.org/wiki/Time%20standard | Time standard | A time standard is a specification for measuring time: either the rate at which time passes or points in time or both. In modern times, several time specifications have been officially recognized as standards, where formerly they were matters of custom and practice. An example of a kind of time standard can be a time s... | Technology | Timekeeping | null |
41811 | https://en.wikipedia.org/wiki/Transmission%20line | Transmission line | In electrical engineering, a transmission line is a specialized cable or other structure designed to conduct electromagnetic waves in a contained manner. The term applies when the conductors are long enough that the wave nature of the transmission must be taken into account. This applies especially to radio-frequency ... | Technology | Signal transmission | null |
41822 | https://en.wikipedia.org/wiki/Troposphere | Troposphere | The troposphere is the lowest layer of the atmosphere of Earth. It contains 80% of the total mass of the planetary atmosphere and 99% of the total mass of water vapor and aerosols, and is where most weather phenomena occur. From the planetary surface of the Earth, the average height of the troposphere is in the tropic... | Physical sciences | Atmosphere: General | Earth science |
41831 | https://en.wikipedia.org/wiki/Telephony | Telephony | Telephony ( ) is the field of technology involving the development, application, and deployment of telecommunications services for the purpose of electronic transmission of voice, fax, or data, between distant parties. The history of telephony is intimately linked to the invention and development of the telephone.
Tel... | Technology | Telecommunications | null |
41863 | https://en.wikipedia.org/wiki/Waveguide | Waveguide | A waveguide is a structure that guides waves by restricting the transmission of energy to one direction. Common types of waveguides include acoustic waveguides which direct sound, optical waveguides which direct light, and radio-frequency waveguides which direct electromagnetic waves other than light like radio waves.
... | Technology | Components | null |
41890 | https://en.wikipedia.org/wiki/Group%20theory | Group theory | In abstract algebra, group theory studies the algebraic structures known as groups.
The concept of a group is central to abstract algebra: other well-known algebraic structures, such as rings, fields, and vector spaces, can all be seen as groups endowed with additional operations and axioms. Groups recur throughout m... | Mathematics | Algebra | null |
41932 | https://en.wikipedia.org/wiki/Accuracy%20and%20precision | Accuracy and precision | Accuracy and precision are two measures of observational error.
Accuracy is how close a given set of measurements (observations or readings) are to their true value.
Precision is how close the measurements are to each other.
The International Organization for Standardization (ISO) defines a related measure:
trueness, ... | Physical sciences | Measurement: General | null |
41957 | https://en.wikipedia.org/wiki/Electrical%20impedance | Electrical impedance | In electrical engineering, impedance is the opposition to alternating current presented by the combined effect of resistance and reactance in a circuit.
Quantitatively, the impedance of a two-terminal circuit element is the ratio of the complex representation of the sinusoidal voltage between its terminals, to the com... | Physical sciences | Electrical circuits | null |
41958 | https://en.wikipedia.org/wiki/Lidar | Lidar | Lidar (, also LIDAR, LiDAR or LADAR, an acronym of "light detection and ranging" or "laser imaging, detection, and ranging") is a method for determining ranges by targeting an object or a surface with a laser and measuring the time for the reflected light to return to the receiver. Lidar may operate in a fixed directio... | Technology | Surveying tools | null |
41968 | https://en.wikipedia.org/wiki/Gain%20%28electronics%29 | Gain (electronics) | In electronics, gain is a measure of the ability of a two-port circuit (often an amplifier) to increase the power or amplitude of a signal from the input to the output port by adding energy converted from some power supply to the signal. It is usually defined as the mean ratio of the signal amplitude or power at the ou... | Physical sciences | Electrical circuits | null |
41985 | https://en.wikipedia.org/wiki/Shortest%20path%20problem | Shortest path problem | In graph theory, the shortest path problem is the problem of finding a path between two vertices (or nodes) in a graph such that the sum of the weights of its constituent edges is minimized.
The problem of finding the shortest path between two intersections on a road map may be modeled as a special case of the shortes... | Mathematics | Graph theory | null |
41993 | https://en.wikipedia.org/wiki/Intensity%20%28physics%29 | Intensity (physics) | In physics and many other areas of science and engineering the intensity or flux of radiant energy is the power transferred per unit area, where the area is measured on the plane perpendicular to the direction of propagation of the energy. In the SI system, it has units watts per square metre (W/m2), or kg⋅s−3 in base ... | Physical sciences | Optics | Physics |
41997 | https://en.wikipedia.org/wiki/Twin%20prime | Twin prime | A twin prime is a prime number that is either 2 less or 2 more than another prime number—for example, either member of the twin prime pair or In other words, a twin prime is a prime that has a prime gap of two. Sometimes the term twin prime is used for a pair of twin primes; an alternative name for this is prime twin... | Mathematics | Prime numbers | null |
42048 | https://en.wikipedia.org/wiki/Plastic%20surgery | Plastic surgery | Plastic surgery is a surgical specialty involving the restoration, reconstruction, or alteration of the human body. It can be divided into two main categories: reconstructive surgery and cosmetic surgery. Reconstructive surgery covers a wide range of specialties, including craniofacial surgery, hand surgery, microsurge... | Biology and health sciences | Medical procedures | null |
42052 | https://en.wikipedia.org/wiki/Mescaline | Mescaline | Mescaline, also known as mescalin or mezcalin, and in chemical terms 3,4,5-trimethoxyphenethylamine, is a naturally occurring psychedelic protoalkaloid of the substituted phenethylamine class, known for its hallucinogenic effects comparable to those of LSD and psilocybin. It binds to and activates certain serotonin rec... | Biology and health sciences | Recreational drugs | Health |
42078 | https://en.wikipedia.org/wiki/Hydrogen%20cyanide | Hydrogen cyanide | Hydrogen cyanide (formerly known as prussic acid) is a chemical compound with the formula HCN and structural formula . It is a highly toxic and flammable liquid that boils slightly above room temperature, at . HCN is produced on an industrial scale and is a highly valued precursor to many chemical compounds ranging fro... | Physical sciences | Hydrogen compounds | Chemistry |
42079 | https://en.wikipedia.org/wiki/Potassium%20ferrocyanide | Potassium ferrocyanide | Potassium hexacyanidoferrate(II) is the inorganic compound with formula K4[Fe(CN)6]·3H2O. It is the potassium salt of the coordination complex [Fe(CN)6]4−. This salt forms lemon-yellow monoclinic crystals.
Synthesis
In 1752, the French chemist Pierre Joseph Macquer (1718–1784) first reported the preparation of Potass... | Physical sciences | Cyanide salts | Chemistry |
42080 | https://en.wikipedia.org/wiki/Atlantic%20cod | Atlantic cod | The Atlantic cod (: cod; Gadus morhua) is a fish of the family Gadidae, widely consumed by humans. It is also commercially known as cod or codling.
In the western Atlantic Ocean, cod has a distribution north of Cape Hatteras, North Carolina, and around both coasts of Greenland and the Labrador Sea; in the eastern Atla... | Biology and health sciences | Acanthomorpha | Animals |
42114 | https://en.wikipedia.org/wiki/Salmonella | Salmonella | Salmonella is a genus of rod-shaped, (bacillus) gram-negative bacteria of the family Enterobacteriaceae. The two known species of Salmonella are Salmonella enterica and Salmonella bongori. S. enterica is the type species and is further divided into six subspecies that include over 2,650 serotypes. Salmonella was named ... | Biology and health sciences | Other organisms | null |
42116 | https://en.wikipedia.org/wiki/Server%20%28computing%29 | Server (computing) | A server is a computer that provides information to other computers called "clients" on a computer network. This architecture is called the client–server model. Servers can provide various functionalities, often called "services", such as sharing data or resources among multiple clients or performing computations for a... | Technology | Networks | null |
42139 | https://en.wikipedia.org/wiki/Garden | Garden | A garden is a planned space, usually outdoors, set aside for the cultivation, display, and enjoyment of plants and other forms of nature. The single feature identifying even the wildest wild garden is control. The garden can incorporate both natural and artificial materials.
Gardens often have design features includin... | Technology | Food and health | null |
42168 | https://en.wikipedia.org/wiki/Data%20communication | Data communication | Data communication, including data transmission and data reception, is the transfer of data, transmitted and received over a point-to-point or point-to-multipoint communication channel. Examples of such channels are copper wires, optical fibers, wireless communication using radio spectrum, storage media and computer bu... | Technology | Basics_3 | null |
42253 | https://en.wikipedia.org/wiki/Data%20mining | Data mining | Data mining is the process of extracting and discovering patterns in large data sets involving methods at the intersection of machine learning, statistics, and database systems. Data mining is an interdisciplinary subfield of computer science and statistics with an overall goal of extracting information (with intellige... | Technology | Computer software | null |
42261 | https://en.wikipedia.org/wiki/Irrigation | Irrigation | Irrigation (also referred to as watering of plants) is the practice of applying controlled amounts of water to land to help grow crops, landscape plants, and lawns. Irrigation has been a key aspect of agriculture for over 5,000 years and has been developed by many cultures around the world. Irrigation helps to grow cro... | Technology | Horticultural techniques | null |
42405 | https://en.wikipedia.org/wiki/Ichthyology | Ichthyology | Ichthyology is the branch of zoology devoted to the study of fish, including bony fish (Osteichthyes), cartilaginous fish (Chondrichthyes), and jawless fish (Agnatha). According to FishBase, 33,400 species of fish had been described as of October 2016, with approximately 250 new species described each year.
Etymology
... | Biology and health sciences | Basics_2 | Biology |
42418 | https://en.wikipedia.org/wiki/Electrical%20cable | Electrical cable | An electrical cable is an assembly of one or more wires running side by side or bundled, which is used as an electrical conductor to carry electric current.
Electrical cables are used to connect two or more devices, enabling the transfer of electrical signals, power, or both from one device to the other. Physically, ... | Technology | Components_2 | null |
42445 | https://en.wikipedia.org/wiki/Dalton%20%28unit%29 | Dalton (unit) | The dalton or unified atomic mass unit (symbols: Da or u, respectively) is a unit of mass defined as of the mass of an unbound neutral atom of carbon-12 in its nuclear and electronic ground state and at rest. It is a non-SI unit accepted for use with SI. The atomic mass constant, denoted mu, is defined identically, gi... | Physical sciences | Mass | null |
42563 | https://en.wikipedia.org/wiki/Polyp%20%28zoology%29 | Polyp (zoology) | A polyp in zoology is one of two forms found in the phylum Cnidaria, the other being the medusa. Polyps are roughly cylindrical in shape and elongated at the axis of the vase-shaped body. In solitary polyps, the aboral (opposite to oral) end is attached to the substrate by means of a disc-like holdfast called a pedal ... | Biology and health sciences | Cnidarians | Animals |
42567 | https://en.wikipedia.org/wiki/Spleen | Spleen | The spleen (, from Ancient Greek σπλήν, splḗn) is an organ found in almost all vertebrates. Similar in structure to a large lymph node, it acts primarily as a blood filter.
The spleen plays important roles in regard to red blood cells (erythrocytes) and the immune system. It removes old red blood cells and holds a r... | Biology and health sciences | Circulatory system | null |
42693 | https://en.wikipedia.org/wiki/Upper%20and%20lower%20bounds | Upper and lower bounds | In mathematics, particularly in order theory, an upper bound or majorant of a subset of some preordered set is an element of that is every element of .
Dually, a lower bound or minorant of is defined to be an element of that is less than or equal to every element of .
A set with an upper (respectively, lower) b... | Mathematics | Order theory | null |
42709 | https://en.wikipedia.org/wiki/Pendulum | Pendulum | A pendulum is a device made of a weight suspended from a pivot so that it can swing freely. When a pendulum is displaced sideways from its resting, equilibrium position, it is subject to a restoring force due to gravity that will accelerate it back toward the equilibrium position. When released, the restoring force act... | Technology | Timekeeping | null |
42726 | https://en.wikipedia.org/wiki/Cephalopod | Cephalopod | A cephalopod is any member of the molluscan class Cephalopoda (Greek plural , ; "head-feet") such as a squid, octopus, cuttlefish, or nautilus. These exclusively marine animals are characterized by bilateral body symmetry, a prominent head, and a set of arms or tentacles (muscular hydrostats) modified from the primit... | Biology and health sciences | Cephalopods | Animals |
42799 | https://en.wikipedia.org/wiki/Speech%20synthesis | Speech synthesis | Speech synthesis is the artificial production of human speech. A computer system used for this purpose is called a speech synthesizer, and can be implemented in software or hardware products. A text-to-speech (TTS) system converts normal language text into speech; other systems render symbolic linguistic representation... | Technology | Media and communication | null |
42806 | https://en.wikipedia.org/wiki/Cyclone | Cyclone | In meteorology, a cyclone () is a large air mass that rotates around a strong center of low atmospheric pressure, counterclockwise in the Northern Hemisphere and clockwise in the Southern Hemisphere as viewed from above (opposite to an anticyclone). Cyclones are characterized by inward-spiraling winds that rotate abou... | Physical sciences | Atmospheric circulation | null |
42852 | https://en.wikipedia.org/wiki/Radio%20frequency | Radio frequency | Radio frequency (RF) is the oscillation rate of an alternating electric current or voltage or of a magnetic, electric or electromagnetic field or mechanical system in the frequency range from around to around . This is roughly between the upper limit of audio frequencies and the lower limit of infrared frequencies, an... | Physical sciences | Waves | Physics |
42888 | https://en.wikipedia.org/wiki/Human%20genome | Human genome | The human genome is a complete set of nucleic acid sequences for humans, encoded as the DNA within each of the 24 distinct chromosomes in the cell nucleus. A small DNA molecule is found within individual mitochondria. These are usually treated separately as the nuclear genome and the mitochondrial genome. Human genomes... | Biology and health sciences | Genetics and taxonomy | null |
42898 | https://en.wikipedia.org/wiki/Anthrax | Anthrax | Anthrax is an infection caused by the bacterium Bacillus anthracis or Bacillus cereus biovar anthracis. Infection typically occurs by contact with the skin, inhalation, or intestinal absorption. Symptom onset occurs between one day and more than two months after the infection is contracted. The skin form presents with ... | Biology and health sciences | Infectious disease | null |
42937 | https://en.wikipedia.org/wiki/Photodiode | Photodiode | A photodiode is a semiconductor diode sensitive to photon radiation, such as visible light, infrared or ultraviolet radiation, X-rays and gamma rays. It produces an electrical current when it absorbs photons. This can be used for detection and measurement applications, or for the generation of electrical power in solar... | Technology | Components | null |
42957 | https://en.wikipedia.org/wiki/Endospore | Endospore | An endospore is a dormant, tough, and non-reproductive structure produced by some bacteria in the phylum Bacillota. The name "endospore" is suggestive of a spore or seed-like form (endo means 'within'), but it is not a true spore (i.e., not an offspring). It is a stripped-down, dormant form to which the bacterium can r... | Biology and health sciences | Basic anatomy | Biology |
42964 | https://en.wikipedia.org/wiki/Snell%27s%20law | Snell's law | Snell's law (also known as the Snell–Descartes law, the ibn-Sahl law, and the law of refraction) is a formula used to describe the relationship between the angles of incidence and refraction, when referring to light or other waves passing through a boundary between two different isotropic media, such as water, glass, ... | Physical sciences | Optics | Physics |
1490711 | https://en.wikipedia.org/wiki/Opah | Opah | Opahs, also commonly known as moonfish, sunfish, cowfish (not to be confused with Molidae), kingfish, and redfin ocean pan are large, colorful, deep-bodied pelagic lampriform fishes comprising the small family Lampridae (also spelled Lamprididae).
The family comprises two genera: Lampris () and the monotypic Megalamp... | Biology and health sciences | Acanthomorpha | Animals |
1491594 | https://en.wikipedia.org/wiki/Giant%20clam | Giant clam | Tridacna gigas, the giant clam, is the best-known species of the giant clam genus Tridacna. Giant clams are the largest living bivalve mollusks. Several other species of "giant clam" in the genus Tridacna are often misidentified as Tridacna gigas.
These clams were known to indigenous peoples of East Asia for thousands... | Biology and health sciences | Bivalvia | Animals |
1491814 | https://en.wikipedia.org/wiki/Electric%20stove | Electric stove | An electric stove, electric cooker or electric range is a stove with an integrated electrical heating device to cook and bake. Electric stoves became popular as replacements for solid-fuel (wood or coal) stoves which required more labor to operate and maintain. Some modern stoves come in a unit with built-in extractor ... | Technology | Household appliances | null |
1493798 | https://en.wikipedia.org/wiki/Eastern%20mole | Eastern mole | The eastern mole or common mole (Scalopus aquaticus) is a medium-sized North American mole. It is the only species in the genus Scalopus. It is found in forested and open areas with moist sandy soils in northern Mexico, the eastern United States and the southwestern corner of Ontario in Canada.
The eastern mole has gr... | Biology and health sciences | Eulipotyphla | Animals |
1494235 | https://en.wikipedia.org/wiki/Glacial%20landform | Glacial landform | Glacial landforms are landforms created by the action of glaciers. Most of today's glacial landforms were created by the movement of large ice sheets during the Quaternary glaciations. Some areas, like Fennoscandia and the southern Andes, have extensive occurrences of glacial landforms; other areas, such as the Sahara,... | Physical sciences | Glacial landforms | null |
1494648 | https://en.wikipedia.org/wiki/Google%20Maps | Google Maps | Google Maps is a web mapping platform and consumer application offered by Google. It offers satellite imagery, aerial photography, street maps, 360° interactive panoramic views of streets (Street View), real-time traffic conditions, and route planning for traveling by foot, car, bike, air (in beta) and public transport... | Technology | Utility | null |
151590 | https://en.wikipedia.org/wiki/Faraday%20cage | Faraday cage | A Faraday cage or Faraday shield is an enclosure used to block some electromagnetic fields. A Faraday shield may be formed by a continuous covering of conductive material, or in the case of a Faraday cage, by a mesh of such materials. Faraday cages are named after scientist Michael Faraday, who first constructed one in... | Technology | Signal transmission | null |
151648 | https://en.wikipedia.org/wiki/Very%20Large%20Telescope | Very Large Telescope | The Very Large Telescope (VLT) is an astronomical facility operated since 1998 by the European Southern Observatory, located on Cerro Paranal in the Atacama Desert of northern Chile. It consists of four individual telescopes, each equipped with a primary mirror that measures 8.2 meters in diameter. These optical telesc... | Technology | Ground-based observatories | null |
151651 | https://en.wikipedia.org/wiki/Fomalhaut | Fomalhaut | Fomalhaut (, ) is the brightest star in the southern constellation of Piscis Austrinus, the Southern Fish, and one of the brightest stars in the night sky. It has the Bayer designation Alpha Piscis Austrini, which is an alternative form of α Piscis Austrini, and is abbreviated Alpha PsA or α PsA. This is a class A star... | Physical sciences | Notable stars | Astronomy |
151783 | https://en.wikipedia.org/wiki/Stirling%27s%20approximation | Stirling's approximation | In mathematics, Stirling's approximation (or Stirling's formula) is an asymptotic approximation for factorials. It is a good approximation, leading to accurate results even for small values of . It is named after James Stirling, though a related but less precise result was first stated by Abraham de Moivre.
One way of... | Mathematics | Specific functions | null |
151828 | https://en.wikipedia.org/wiki/Side%20effect | Side effect | In medicine, a side effect is an effect of the use of a medicinal drug or other treatment, usually adverse but sometimes beneficial, that is unintended. Herbal and traditional medicines also have side effects.
A drug or procedure usually used for a specific effect may be used specifically because of a beneficial side... | Biology and health sciences | General concepts_2 | Health |
151864 | https://en.wikipedia.org/wiki/Divergence%20theorem | Divergence theorem | In vector calculus, the divergence theorem, also known as Gauss's theorem or Ostrogradsky's theorem, is a theorem relating the flux of a vector field through a closed surface to the divergence of the field in the volume enclosed.
More precisely, the divergence theorem states that the surface integral of a vector field... | Mathematics | Multivariable and vector calculus | null |
151925 | https://en.wikipedia.org/wiki/Del | Del | Del, or nabla, is an operator used in mathematics (particularly in vector calculus) as a vector differential operator, usually represented by the nabla symbol ∇. When applied to a function defined on a one-dimensional domain, it denotes the standard derivative of the function as defined in calculus. When applied to a f... | Mathematics | Calculus and analysis | null |
151942 | https://en.wikipedia.org/wiki/Vaccinium%20vitis-idaea | Vaccinium vitis-idaea | Vaccinium vitis-idaea is a small evergreen shrub in the heath family, Ericaceae. It is known colloquially as the lingonberry, partridgeberry, foxberry, mountain cranberry, or cowberry. It is native to boreal forest and Arctic tundra throughout the Northern Hemisphere. Commercially cultivated in the United States Pacifi... | Biology and health sciences | Berries | Plants |
151965 | https://en.wikipedia.org/wiki/Vernalization | Vernalization | Vernalization () is the induction of a plant's flowering process by exposure to the prolonged cold of winter, or by an artificial equivalent. After vernalization, plants have acquired the ability to flower, but they may require additional seasonal cues or weeks of growth before they will actually do so. The term is som... | Biology and health sciences | Plant reproduction | Biology |
152030 | https://en.wikipedia.org/wiki/Corvette | Corvette | A corvette is a small warship. It is traditionally the smallest class of vessel considered to be a proper (or "rated") warship. The warship class above the corvette is that of the frigate, while the class below was historically that of the sloop-of-war.
The modern roles that a corvette fulfills include coastal patrol ... | Technology | Naval warfare | null |
152205 | https://en.wikipedia.org/wiki/Forcing%20%28mathematics%29 | Forcing (mathematics) | In the mathematical discipline of set theory, forcing is a technique for proving consistency and independence results. Intuitively, forcing can be thought of as a technique to expand the set theoretical universe to a larger universe by introducing a new "generic" object .
Forcing was first used by Paul Cohen in 1963... | Mathematics | Set theory | null |
152207 | https://en.wikipedia.org/wiki/Compactness%20theorem | Compactness theorem | In mathematical logic, the compactness theorem states that a set of first-order sentences has a model if and only if every finite subset of it has a model. This theorem is an important tool in model theory, as it provides a useful (but generally not effective) method for constructing models of any set of sentences that... | Mathematics | Model theory | null |
152214 | https://en.wikipedia.org/wiki/Zermelo%E2%80%93Fraenkel%20set%20theory | Zermelo–Fraenkel set theory | In set theory, Zermelo–Fraenkel set theory, named after mathematicians Ernst Zermelo and Abraham Fraenkel, is an axiomatic system that was proposed in the early twentieth century in order to formulate a theory of sets free of paradoxes such as Russell's paradox. Today, Zermelo–Fraenkel set theory, with the historicall... | Mathematics | Axiomatic systems | null |
152288 | https://en.wikipedia.org/wiki/Persimmon | Persimmon | The persimmon () is the edible fruit of a number of species of trees in the genus Diospyros. The most widely cultivated of these is the kaki persimmon, Diospyros kaki Diospyros is in the family Ebenaceae, and a number of non-persimmon species of the genus are grown for ebony timber. In 2022, China produced 77% of the ... | Biology and health sciences | Tropical and tropical-like fruit | Plants |
152393 | https://en.wikipedia.org/wiki/Bulbul | Bulbul | The bulbuls are members of a family, Pycnonotidae, of medium-sized passerine songbirds, which also includes greenbuls, brownbuls, leafloves, and bristlebills. The family is distributed across most of Africa and into the Middle East, tropical Asia to Indonesia, and north as far as Japan. A few insular species occur on t... | Biology and health sciences | Passerida | null |
152440 | https://en.wikipedia.org/wiki/Stellar%20nucleosynthesis | Stellar nucleosynthesis | In astrophysics, stellar nucleosynthesis is the creation of chemical elements by nuclear fusion reactions within stars. Stellar nucleosynthesis has occurred since the original creation of hydrogen, helium and lithium during the Big Bang. As a predictive theory, it yields accurate estimates of the observed abundances of... | Physical sciences | Stellar astronomy | Astronomy |
152464 | https://en.wikipedia.org/wiki/Nuclide | Nuclide | Nuclides (or nucleides, from nucleus, also known as nuclear species) are a class of atoms characterized by their number of protons, Z, their number of neutrons, N, and their nuclear energy state.
The word nuclide was coined by the American nuclear physicist Truman P. Kohman in 1947. Kohman defined nuclide as a "specie... | Physical sciences | Chemistry: General | null |
152465 | https://en.wikipedia.org/wiki/Optic%20nerve | Optic nerve | In neuroanatomy, the optic nerve, also known as the second cranial nerve, cranial nerve II, or simply CN II, is a paired cranial nerve that transmits visual information from the retina to the brain. In humans, the optic nerve is derived from optic stalks during the seventh week of development and is composed of retinal... | Biology and health sciences | Visual system | Biology |
152509 | https://en.wikipedia.org/wiki/Metastasis | Metastasis | Metastasis is a pathogenic agent's spreading from an initial or primary site to a different or secondary site within the host's body; the term is typically used when referring to metastasis by a cancerous tumor. The newly pathological sites, then, are metastases (mets). It is generally distinguished from cancer invasi... | Biology and health sciences | Cancer | Health |
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