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52135
https://en.wikipedia.org/wiki/Pneumonia
Pneumonia
Pneumonia is an inflammatory condition of the lung primarily affecting the small air sacs known as alveoli. Symptoms typically include some combination of productive or dry cough, chest pain, fever, and difficulty breathing. The severity of the condition is variable. Pneumonia is usually caused by infection with virus...
Biology and health sciences
Illness and injury
null
52136
https://en.wikipedia.org/wiki/Citrus
Citrus
Citrus is a genus of flowering trees and shrubs in the family Rutaceae. Plants in the genus produce citrus fruits, including important crops such as oranges, mandarins, lemons, grapefruits, pomelos, and limes. Citrus is native to South Asia, East Asia, Southeast Asia, Melanesia, and Australia. Indigenous people in the...
Biology and health sciences
Sapindales
null
52202
https://en.wikipedia.org/wiki/Magic%20square
Magic square
In mathematics, especially historical and recreational mathematics, a square array of numbers, usually positive integers, is called a magic square if the sums of the numbers in each row, each column, and both main diagonals are the same. The "order" of the magic square is the number of integers along one side (n), and ...
Mathematics
Sums and products
null
52247
https://en.wikipedia.org/wiki/Fourier%20transform
Fourier transform
In mathematics, the Fourier transform (FT) is an integral transform that takes a function as input and outputs another function that describes the extent to which various frequencies are present in the original function. The output of the transform is a complex-valued function of frequency. The term Fourier transform r...
Mathematics
Calculus and analysis
null
52255
https://en.wikipedia.org/wiki/Wild%20boar
Wild boar
The wild boar (Sus scrofa), also known as the wild swine, common wild pig, Eurasian wild pig, or simply wild pig, is a suid native to much of Eurasia and North Africa, and has been introduced to the Americas and Oceania. The species is now one of the widest-ranging mammals in the world, as well as the most widespread s...
Biology and health sciences
Artiodactyla
null
52316
https://en.wikipedia.org/wiki/Mood%20disorder
Mood disorder
A mood disorder, also known as an affective disorder, is any of a group of conditions of mental and behavioral disorder where the main underlying characteristic is a disturbance in the person's mood. The classification is in the Diagnostic and Statistical Manual of Mental Disorders (DSM) and International Classificatio...
Biology and health sciences
Mental disorders
Health
52358
https://en.wikipedia.org/wiki/Imaginary%20unit
Imaginary unit
The imaginary unit or unit imaginary number () is a mathematical constant that is a solution to the quadratic equation Although there is no real number with this property, can be used to extend the real numbers to what are called complex numbers, using addition and multiplication. A simple example of the use of in a...
Mathematics
Basics
null
52376
https://en.wikipedia.org/wiki/Axiom%20of%20extensionality
Axiom of extensionality
The axiom of extensionality, also called the axiom of extent, is an axiom used in many forms of axiomatic set theory, such as Zermelo–Fraenkel set theory. The axiom defines what a set is. Informally, the axiom means that the two sets A and B are equal if and only if A and B have the same members. In ZF set theory In ...
Mathematics
Axiomatic systems
null
52385
https://en.wikipedia.org/wiki/Axiom%20of%20pairing
Axiom of pairing
In axiomatic set theory and the branches of logic, mathematics, and computer science that use it, the axiom of pairing is one of the axioms of Zermelo–Fraenkel set theory. It was introduced by as a special case of his axiom of elementary sets. Formal statement In the formal language of the Zermelo–Fraenkel axioms, t...
Mathematics
Axiomatic systems
null
52386
https://en.wikipedia.org/wiki/Axiom%20schema%20of%20specification
Axiom schema of specification
In many popular versions of axiomatic set theory, the axiom schema of specification, also known as the axiom schema of separation (Aussonderungsaxiom), subset axiom, axiom of class construction, or axiom schema of restricted comprehension is an axiom schema. Essentially, it says that any definable subclass of a set is...
Mathematics
Axiomatic systems
null
52387
https://en.wikipedia.org/wiki/Axiom%20schema%20of%20replacement
Axiom schema of replacement
In set theory, the axiom schema of replacement is a schema of axioms in Zermelo–Fraenkel set theory (ZF) that asserts that the image of any set under any definable mapping is also a set. It is necessary for the construction of certain infinite sets in ZF. The axiom schema is motivated by the idea that whether a class ...
Mathematics
Axiomatic systems
null
52432
https://en.wikipedia.org/wiki/Xanthine
Xanthine
Xanthine ( or , from Ancient Greek for its yellowish-white appearance; archaically xanthic acid; systematic name 3,7-dihydropurine-2,6-dione) is a purine base found in most human body tissues and fluids, as well as in other organisms. Several stimulants are derived from xanthine, including caffeine, theophylline, an...
Physical sciences
Alkaloids
Chemistry
52552
https://en.wikipedia.org/wiki/Axiom%20of%20power%20set
Axiom of power set
In mathematics, the axiom of power set is one of the Zermelo–Fraenkel axioms of axiomatic set theory. It guarantees for every set the existence of a set , the power set of , consisting precisely of the subsets of . By the axiom of extensionality, the set is unique. The axiom of power set appears in most axiomatizati...
Mathematics
Axiomatic systems
null
52553
https://en.wikipedia.org/wiki/Axiom%20of%20union
Axiom of union
In axiomatic set theory, the axiom of union is one of the axioms of Zermelo–Fraenkel set theory. This axiom was introduced by Ernst Zermelo. Informally, the axiom states that for each set x there is a set y whose elements are precisely the elements of the elements of x. Formal statement In the formal language of the...
Mathematics
Axiomatic systems
null
52564
https://en.wikipedia.org/wiki/Partial%20differential%20equation
Partial differential equation
In mathematics, a partial differential equation (PDE) is an equation which involves a multivariable function and one or more of its partial derivatives. The function is often thought of as an "unknown" that solves the equation, similar to how is thought of as an unknown number solving, e.g., an algebraic equation lik...
Mathematics
Calculus and analysis
null
52565
https://en.wikipedia.org/wiki/Partial%20derivative
Partial derivative
In mathematics, a partial derivative of a function of several variables is its derivative with respect to one of those variables, with the others held constant (as opposed to the total derivative, in which all variables are allowed to vary). Partial derivatives are used in vector calculus and differential geometry. Th...
Mathematics
Calculus and analysis
null
52636
https://en.wikipedia.org/wiki/Boiling
Boiling
Boiling or ebullition is the rapid phase transition from liquid to gas or vapour; the reverse of boiling is condensation. Boiling occurs when a liquid is heated to its boiling point, so that the vapour pressure of the liquid is equal to the pressure exerted on the liquid by the surrounding atmosphere. Boiling and evapo...
Physical sciences
Phase transitions
null
52644
https://en.wikipedia.org/wiki/Cysteine
Cysteine
Cysteine (; symbol Cys or C) is a semiessential proteinogenic amino acid with the formula . The thiol side chain in cysteine enables the formation of disulfide bonds, and often participates in enzymatic reactions as a nucleophile. Cysteine is chiral, but both D and L-cysteine are found in nature. LCysteine is a protein...
Biology and health sciences
Amino acids
Biology
52648
https://en.wikipedia.org/wiki/Camera
Camera
A camera is an instrument used to capture and store images and videos, either digitally via an electronic image sensor, or chemically via a light-sensitive material such as photographic film. As a pivotal technology in the fields of photography and videography, cameras have played a significant role in the progression ...
Technology
Optical
null
52649
https://en.wikipedia.org/wiki/Acetylcholine
Acetylcholine
Acetylcholine (ACh) is an organic compound that functions in the brain and body of many types of animals (including humans) as a neurotransmitter. Its name is derived from its chemical structure: it is an ester of acetic acid and choline. Parts in the body that use or are affected by acetylcholine are referred to as ch...
Biology and health sciences
Neurotransmitters
Biology
52713
https://en.wikipedia.org/wiki/Binary%20star
Binary star
A binary star or binary star system is a system of two stars that are gravitationally bound to and in orbit around each other. Binary stars in the night sky that are seen as a single object to the naked eye are often resolved as separate stars using a telescope, in which case they are called visual binaries. Many visua...
Physical sciences
Stellar astronomy
null
52742
https://en.wikipedia.org/wiki/Desktop%20computer
Desktop computer
A desktop computer, often abbreviated as desktop, is a personal computer designed for regular use at a stationary location on or near a desk (as opposed to a portable computer) due to its size and power requirements. The most common configuration has a case that houses the power supply, motherboard (a printed circuit b...
Technology
Computer hardware
null
52778
https://en.wikipedia.org/wiki/Sodium%20cyanide
Sodium cyanide
Sodium cyanide is a compound with the formula NaCN and the structure . It is a white, water-soluble solid. Cyanide has a high affinity for metals, which leads to the high toxicity of this salt. Its main application, in gold mining, also exploits its high reactivity toward metals. It is a moderately strong base. Produc...
Physical sciences
Cyanide salts
Chemistry
52812
https://en.wikipedia.org/wiki/Humidity
Humidity
Humidity is the concentration of water vapor present in the air. Water vapor, the gaseous state of water, is generally invisible to the human eye. Humidity indicates the likelihood for precipitation, dew, or fog to be present. Humidity depends on the temperature and pressure of the system of interest. The same amount ...
Physical sciences
Meteorology: General
null
52838
https://en.wikipedia.org/wiki/Charon%20%28moon%29
Charon (moon)
Charon ( or ), or (134340) Pluto I, is the largest of the five known natural satellites of the dwarf planet Pluto. It has a mean radius of . Charon is the sixth-largest known trans-Neptunian object after Pluto, Eris, Haumea, Makemake, and Gonggong. It was discovered in 1978 at the United States Naval Observatory in W...
Physical sciences
Solar System
Astronomy
52866
https://en.wikipedia.org/wiki/Cooking%20weights%20and%20measures
Cooking weights and measures
In recipes, quantities of ingredients may be specified by mass (commonly called weight), by volume, or by count. For most of history, most cookbooks did not specify quantities precisely, instead talking of "a nice leg of spring lamb", a "cupful" of lentils, a piece of butter "the size of a small apricot", and "suffici...
Physical sciences
Measurement systems
Basics and measurement
52957
https://en.wikipedia.org/wiki/Bell%27s%20palsy
Bell's palsy
Bell's palsy is a type of facial paralysis that results in a temporary inability to control the facial muscles on the affected side of the face. In most cases, the weakness is temporary and significantly improves over weeks. Symptoms can vary from mild to severe. They may include muscle twitching, weakness, or total lo...
Biology and health sciences
Disabilities
Health
52963
https://en.wikipedia.org/wiki/Obstetrics%20and%20gynaecology
Obstetrics and gynaecology
Obstetrics and gynaecology (also spelled as obstetrics and gynecology; abbreviated as Obst and Gynae, O&G, OB-GYN and OB/GYN) is the medical specialty that encompasses the two subspecialties of obstetrics (covering pregnancy, childbirth, and the postpartum period) and gynaecology (covering the health of the female repr...
Biology and health sciences
Fields of medicine
null
52965
https://en.wikipedia.org/wiki/Obstetrics
Obstetrics
Obstetrics is the field of study concentrated on pregnancy, childbirth and the postpartum period. As a medical specialty, obstetrics is combined with gynecology under the discipline known as obstetrics and gynecology (OB/GYN), which is a surgical field. Main areas Prenatal care Prenatal care is important in screenin...
Biology and health sciences
Fields of medicine
Health
52967
https://en.wikipedia.org/wiki/Gynaecology
Gynaecology
Gynaecology or gynecology (see American and British English spelling differences) is the area of medicine that involves the treatment of women's diseases, especially those of the female reproductive organs. It is often paired with the field of obstetrics, which focuses on pregnancy and childbirth, thereby forming the c...
Biology and health sciences
Fields of medicine
Health
52974
https://en.wikipedia.org/wiki/Emergency%20medicine
Emergency medicine
Emergency medicine is the medical specialty concerned with the care of illnesses or injuries requiring immediate medical attention. Emergency medicine physicians (often called "ER doctors" in the United States) specialize in providing care for unscheduled and undifferentiated patients of all ages. As first-line provide...
Biology and health sciences
Fields of medicine
Health
52975
https://en.wikipedia.org/wiki/Emergency%20medical%20services
Emergency medical services
Emergency medical services (EMS), also known as ambulance services, pre-hospital care or paramedic services, are emergency services that provide urgent pre-hospital treatment and stabilisation for serious illness and injuries and transport to definitive care. They may also be known as a first aid squad, FAST squad, eme...
Biology and health sciences
General concepts
null
52999
https://en.wikipedia.org/wiki/Phobos%20%28moon%29
Phobos (moon)
Phobos (; systematic designation: ) is the innermost and larger of the two natural satellites of Mars, the other being Deimos. The two moons were discovered in 1877 by American astronomer Asaph Hall. Phobos is named after the Greek god of fear and panic, who is the son of Ares (Mars) and twin brother of Deimos. Phobos...
Physical sciences
Solar System
Astronomy
53031
https://en.wikipedia.org/wiki/Stefan%E2%80%93Boltzmann%20law
Stefan–Boltzmann law
The Stefan–Boltzmann law, also known as Stefan's law, describes the intensity of the thermal radiation emitted by matter in terms of that matter's temperature. It is named for Josef Stefan, who empirically derived the relationship, and Ludwig Boltzmann who derived the law theoretically. For an ideal absorber/emitter ...
Physical sciences
Thermodynamics
Physics
53039
https://en.wikipedia.org/wiki/Key%20%28cryptography%29
Key (cryptography)
A key in cryptography is a piece of information, usually a string of numbers or letters that are stored in a file, which, when processed through a cryptographic algorithm, can encode or decode cryptographic data. Based on the used method, the key can be different sizes and varieties, but in all cases, the strength of t...
Technology
Computer security
null
53042
https://en.wikipedia.org/wiki/Symmetric-key%20algorithm
Symmetric-key algorithm
Symmetric-key algorithms are algorithms for cryptography that use the same cryptographic keys for both the encryption of plaintext and the decryption of ciphertext. The keys may be identical, or there may be a simple transformation to go between the two keys. The keys, in practice, represent a shared secret between two...
Technology
Computer security
null
53045
https://en.wikipedia.org/wiki/File%20Allocation%20Table
File Allocation Table
File Allocation Table (FAT) is a file system developed for personal computers and was the default filesystem for the MS-DOS and Windows 9x operating systems. Originally developed in 1977 for use on floppy disks, it was adapted for use on hard disks and other devices. The increase in disk drive capacity over time drove ...
Technology
Data storage and memory
null
53136
https://en.wikipedia.org/wiki/Weapon%20of%20mass%20destruction
Weapon of mass destruction
A weapon of mass destruction (WMD) is a biological, chemical, radiological, nuclear, or any other weapon that can kill or significantly harm many people or cause great damage to artificial structures (e.g., buildings), natural structures (e.g., mountains), or the biosphere. The scope and usage of the term has evolved a...
Technology
Weapons of mass destruction
null
53179
https://en.wikipedia.org/wiki/Boeing%20B-29%20Superfortress
Boeing B-29 Superfortress
The Boeing B-29 Superfortress was an American four-engined propeller-driven heavy bomber, designed by Boeing and flown primarily by the United States during World War II and the Korean War. Named in allusion to its predecessor, the Boeing B-17 Flying Fortress, the Superfortress was designed for high-altitude strategic ...
Technology
Specific aircraft
null
53217
https://en.wikipedia.org/wiki/Exotic%20atom
Exotic atom
An exotic atom is an otherwise normal atom in which one or more sub-atomic particles have been replaced by other particles. For example, electrons may be replaced by other negatively charged particles such as muons (muonic atoms) or pions (pionic atoms). Because these substitute particles are usually unstable, exotic a...
Physical sciences
Atomic physics
Physics
53227
https://en.wikipedia.org/wiki/Vein
Vein
Veins () are blood vessels in the circulatory system of humans and most other animals that carry blood towards the heart. Most veins carry deoxygenated blood from the tissues back to the heart; exceptions are those of the pulmonary and fetal circulations which carry oxygenated blood to the heart. In the systemic circul...
Biology and health sciences
Circulatory system
null
53234
https://en.wikipedia.org/wiki/Face
Face
The face is the front of an animal's head that features the eyes, nose and mouth, and through which animals express many of their emotions. The face is crucial for human identity, and damage such as scarring or developmental deformities may affect the psyche adversely. Structure The front of the human head is called t...
Biology and health sciences
Human anatomy
null
53235
https://en.wikipedia.org/wiki/Neck
Neck
The neck is the part of the body in many vertebrates that connects the head to the torso. It supports the weight of the head and protects the nerves that transmit sensory and motor information between the brain and the rest of the body. Additionally, the neck is highly flexible, allowing the head to turn and move in al...
Biology and health sciences
External anatomy and regions of the body
Biology
53238
https://en.wikipedia.org/wiki/Arm
Arm
In human anatomy, the arm refers to the upper limb in common usage, although academically the term specifically means the upper arm between the glenohumeral joint (shoulder joint) and the elbow joint. The distal part of the upper limb between the elbow and the radiocarpal joint (wrist joint) is known as the forearm or...
Biology and health sciences
Human anatomy
null
53268
https://en.wikipedia.org/wiki/Convolution%20theorem
Convolution theorem
In mathematics, the convolution theorem states that under suitable conditions the Fourier transform of a convolution of two functions (or signals) is the product of their Fourier transforms. More generally, convolution in one domain (e.g., time domain) equals point-wise multiplication in the other domain (e.g., frequen...
Mathematics
Harmonic analysis
null
53288
https://en.wikipedia.org/wiki/Araceae
Araceae
The Araceae are a family of monocotyledonous flowering plants in which flowers are borne on a type of inflorescence called a spadix. The spadix is usually accompanied by, and sometimes partially enclosed in, a spathe (or leaf-like bract). Also known as the arum family, members are often colloquially known as aroids. Th...
Biology and health sciences
Monocots
null
53289
https://en.wikipedia.org/wiki/File%20Transfer%20Protocol
File Transfer Protocol
The File Transfer Protocol (FTP) is a standard communication protocol used for the transfer of computer files from a server to a client on a computer network. FTP is built on a client–server model architecture using separate control and data connections between the client and the server. FTP users may authenticate them...
Technology
Internet
null
53292
https://en.wikipedia.org/wiki/Coca
Coca
Coca is any of the four cultivated plants in the family Erythroxylaceae, native to western South America. Coca is known worldwide for its psychoactive alkaloid, cocaine. Different early-Holocene peoples in different areas of South America independently transformed Erythroxylum gracilipes plants into quotidian stimulan...
Biology and health sciences
Malpighiales
Plants
53306
https://en.wikipedia.org/wiki/Natural%20satellite
Natural satellite
A natural satellite is, in the most common usage, an astronomical body that orbits a planet, dwarf planet, or small Solar System body (or sometimes another natural satellite). Natural satellites are colloquially referred to as moons, a derivation from the Moon of Earth. In the Solar System, there are six planetary sat...
Physical sciences
Astronomy
null
53307
https://en.wikipedia.org/wiki/Lepidoptera
Lepidoptera
Lepidoptera ( ) or lepidopterans is an order of winged insects which includes butterflies and moths. About 180,000 species of the Lepidoptera have been described, representing 10% of the total described species of living organisms, making it the second largest insect order (behind Coleoptera) with 126 families and 46 s...
Biology and health sciences
Lepidoptera
null
53309
https://en.wikipedia.org/wiki/Psychedelic%20drug
Psychedelic drug
Psychedelics are a subclass of hallucinogenic drugs whose primary effect is to trigger non-ordinary mental states (known as psychedelic experiences or "trips") and a perceived "expansion of consciousness". Also referred to as classic hallucinogens or serotonergic hallucinogens, the term psychedelic is sometimes used mo...
Biology and health sciences
Recreational drugs
Health
53332
https://en.wikipedia.org/wiki/Saffron
Saffron
Saffron () is a spice derived from the flower of Crocus sativus, commonly known as the "saffron crocus". The vivid crimson stigma and styles, called threads, are collected and dried for use mainly as a seasoning and colouring agent in food. The saffron crocus was slowly propagated throughout much of Eurasia and was lat...
Biology and health sciences
Monocots
null
53335
https://en.wikipedia.org/wiki/Endometriosis
Endometriosis
Endometriosis is a disease in which cells like those in the endometrium, the layer of tissue that normally covers the inside of the uterus, grow outside the uterus. It occurs in humans and a limited number of menstruating mammals. Endometrial tissue most often grows on or around reproductive organs such as the ovaries ...
Biology and health sciences
Specific diseases
Health
53338
https://en.wikipedia.org/wiki/Cervical%20cancer
Cervical cancer
Cervical cancer is a cancer arising from the cervix or in any layer of the wall of the cervix. It is due to the abnormal growth of cells that have the ability to invade or spread to other parts of the body. Early on, typically no symptoms are seen. Later symptoms may include abnormal vaginal bleeding, pelvic pain or pa...
Biology and health sciences
Cancer
Health
53436
https://en.wikipedia.org/wiki/Bayonet
Bayonet
A bayonet (from Old French , now spelt ) is a knife, dagger, sword, or spike-shaped melee weapon designed to be mounted on the end of the barrel of a rifle, carbine, musket or similar long firearm, allowing the gun to be used as an improvised spear in close combat. The term is derived from the town of Bayonne in south...
Technology
Melee weapons
null
53452
https://en.wikipedia.org/wiki/Euler%27s%20totient%20function
Euler's totient function
In number theory, Euler's totient function counts the positive integers up to a given integer that are relatively prime to . It is written using the Greek letter phi as or , and may also be called Euler's phi function. In other words, it is the number of integers in the range for which the greatest common divisor ...
Mathematics
Specific functions
null
53453
https://en.wikipedia.org/wiki/Fermat%27s%20little%20theorem
Fermat's little theorem
In number theory, Fermat's little theorem states that if is a prime number, then for any integer , the number is an integer multiple of . In the notation of modular arithmetic, this is expressed as For example, if and , then , and is an integer multiple of . If is not divisible by , that is, if is coprime to , ...
Mathematics
Modular arithmetic
null
53455
https://en.wikipedia.org/wiki/Minkowski%27s%20theorem
Minkowski's theorem
In mathematics, Minkowski's theorem is the statement that every convex set in which is symmetric with respect to the origin and which has volume greater than contains a non-zero integer point (meaning a point in that is not the origin). The theorem was proved by Hermann Minkowski in 1889 and became the foundation of...
Mathematics
Other
null
53457
https://en.wikipedia.org/wiki/Quinoa
Quinoa
Quinoa (Chenopodium quinoa; , from Quechua or ) is a flowering plant in the amaranth family. It is a herbaceous annual plant grown as a crop primarily for its edible seeds; the seeds are rich in protein, dietary fiber, B vitamins and dietary minerals in amounts greater than in many grains. Quinoa is not a grass but ra...
Biology and health sciences
Caryophyllales
null
53460
https://en.wikipedia.org/wiki/Statcoulomb
Statcoulomb
The statcoulomb (statC), franklin (Fr), or electrostatic unit of charge (esu) is the unit of measurement for electrical charge used in the centimetre–gram–second electrostatic units variant (CGS-ESU) and Gaussian systems of units. In terms of the Gaussian base units, it is That is, it is defined so that the proportion...
Physical sciences
Charge
Basics and measurement
53464
https://en.wikipedia.org/wiki/Cinnabar
Cinnabar
Cinnabar (; ), or cinnabarite (), also known as mercurblende is the bright scarlet to brick-red form of mercury(II) sulfide (HgS). It is the most common source ore for refining elemental mercury and is the historic source for the brilliant red or scarlet pigment termed vermilion and associated red mercury pigments. Ci...
Physical sciences
Minerals
Earth science
53469
https://en.wikipedia.org/wiki/Cinnamon
Cinnamon
Cinnamon is a spice obtained from the inner bark of several tree species from the genus Cinnamomum. Cinnamon is used mainly as an aromatic condiment and flavouring additive in a wide variety of cuisines, sweet and savoury dishes, breakfast cereals, snack foods, bagels, teas, hot chocolate and traditional foods. The aro...
Biology and health sciences
Magnoliids
null
53479
https://en.wikipedia.org/wiki/2060%20Chiron
2060 Chiron
2060 Chiron is a ringed small Solar System body in the outer Solar System, orbiting the Sun between Saturn and Uranus. Discovered in 1977 by Charles Kowal, it was the first-identified member of a new class of objects now known as centaurs—bodies orbiting between the asteroid belt and the Kuiper belt. Chiron is named af...
Physical sciences
Solar System
Astronomy
53484
https://en.wikipedia.org/wiki/Narwhal
Narwhal
The narwhal (Monodon monoceros) is a species of toothed whale native to the Arctic. It is the only member of the genus Monodon and one of two living representatives of the family Monodontidae. The narwhal is a stocky cetacean with a relatively blunt snout, a large melon, and a shallow ridge in place of a dorsal fin. Ma...
Biology and health sciences
Toothed whale
Animals
53539
https://en.wikipedia.org/wiki/Soyuz%20programme
Soyuz programme
The Soyuz programme ( , ; , meaning "Union") is a human spaceflight programme initiated by the Soviet Union in the early 1960s. The Soyuz spacecraft was originally part of a Moon landing project intended to put a Soviet cosmonaut on the Moon. It was the third Soviet human spaceflight programme after the Vostok (1961–...
Technology
Programs and launch sites
null
53551
https://en.wikipedia.org/wiki/Charadriiformes
Charadriiformes
Charadriiformes (, from Charadrius, the type genus of family Charadriidae) is a diverse order of small to medium-large birds. It includes about 390 species and has members in all parts of the world. Most charadriiform birds live near water and eat invertebrates or other small animals; however, some are pelagic (seabird...
Biology and health sciences
Charadriiformes
Animals
53560
https://en.wikipedia.org/wiki/Procellariiformes
Procellariiformes
Procellariiformes is an order of seabirds that comprises four families: the albatrosses, the petrels and shearwaters, and two families of storm petrels. Formerly called Tubinares and still called tubenoses in English, procellariiforms are often referred to collectively as the petrels, a term that has been applied to a...
Biology and health sciences
Procellariiformes
null
53601
https://en.wikipedia.org/wiki/Metal%20casting
Metal casting
In metalworking and jewelry making, casting is a process in which a liquid metal is delivered into a mold (usually by a crucible) that contains a negative impression (i.e., a three-dimensional negative image) of the intended shape. The metal is poured into the mold through a hollow channel called a sprue. The metal and...
Technology
Metallurgy
null
53603
https://en.wikipedia.org/wiki/Double%20star
Double star
In observational astronomy, a double star or visual double is a pair of stars that appear close to each other as viewed from Earth, especially with the aid of optical telescopes. This occurs because the pair either forms a binary star (i.e. a binary system of stars in mutual orbit, gravitationally bound to each other)...
Physical sciences
Stellar astronomy
Astronomy
53620
https://en.wikipedia.org/wiki/Puffin
Puffin
Puffins are any of three species of small alcids (auks) in the bird genus Fratercula. These are pelagic seabirds that feed primarily by diving in the water. They breed in large colonies on coastal cliffs or offshore islands, nesting in crevices among rocks or in burrows in the soil. Two species, the tufted puffin and h...
Biology and health sciences
Charadriiformes
Animals
53622
https://en.wikipedia.org/wiki/Auk
Auk
Auks or alcids are birds of the family Alcidae in the order Charadriiformes. The alcid family includes the murres, guillemots, auklets, puffins, and murrelets. The family contains 25 extant or recently extinct species that are divided into 11 genera. Auks are found throughout the Northern Hemisphere. Apart from the e...
Biology and health sciences
Charadriiformes
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53631
https://en.wikipedia.org/wiki/Grylloblattidae
Grylloblattidae
Grylloblattidae, commonly known as the icebugs or ice crawlers, is a family of extremophile (psychrophile) and wingless insects that live in the cold on top of mountains and the edges of glaciers. It is the only member of Grylloblattodea, which is generally considered an order. Alternatively, Grylloblattodea, along wit...
Biology and health sciences
Insects: General
Animals
53635
https://en.wikipedia.org/wiki/Odonata
Odonata
Odonata is an order of predatory flying insects that includes the dragonflies and damselflies (as well as the Epiophlebia damsel-dragonflies). The two major groups are distinguished with dragonflies (Anisoptera) usually being bulkier with large compound eyes together and wings spread up or out at rest, while damselflie...
Biology and health sciences
Odonata
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53662
https://en.wikipedia.org/wiki/Peccary
Peccary
Peccaries (also javelinas or skunk pigs) are pig-like ungulates of the family Tayassuidae (New World pigs). They are found throughout Central and South America, Trinidad in the Caribbean, and in the southwestern area of North America. Peccaries usually measure between in length, and a full-grown adult usually weighs a...
Biology and health sciences
Artiodactyla
null
53664
https://en.wikipedia.org/wiki/Kingdom%20%28biology%29
Kingdom (biology)
In biology, a kingdom is the second highest taxonomic rank, just below domain. Kingdoms are divided into smaller groups called phyla (singular phylum). Traditionally, textbooks from Canada and the United States have used a system of six kingdoms (Animalia, Plantae, Fungi, Protista, Archaea/Archaebacteria, and Bacteria...
Biology and health sciences
Genetics and taxonomy
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53686
https://en.wikipedia.org/wiki/Archimedes%27%20screw
Archimedes' screw
The Archimedes' screw, also known as the Archimedean screw, hydrodynamic screw, water screw or Egyptian screw, is one of the earliest hydraulic machines named after Greek mathematician Archimedes who first described it around 234 BC, although the device had been used in Ancient Egypt. It is a reversible hydraulic machi...
Technology
Agricultural tools
null
53694
https://en.wikipedia.org/wiki/Pig%20iron
Pig iron
Pig iron, also known as crude iron, is an intermediate good used by the iron industry in the production of steel. It is developed by smelting iron ore in a blast furnace. Pig iron has a high carbon content, typically 3.8–4.7%, along with silica and other dross, which makes it brittle and not useful directly as a materi...
Physical sciences
Iron alloys
Chemistry
53696
https://en.wikipedia.org/wiki/Division%20%28mathematics%29
Division (mathematics)
Division is one of the four basic operations of arithmetic. The other operations are addition, subtraction, and multiplication. What is being divided is called the dividend, which is divided by the divisor, and the result is called the quotient. At an elementary level the division of two natural numbers is, among oth...
Mathematics
Basics
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53700
https://en.wikipedia.org/wiki/Universal%20Product%20Code
Universal Product Code
The Universal Product Code (UPC or UPC code) is a barcode symbology that is used worldwide for tracking trade items in stores. The chosen symbology has bars (or spaces) of exactly 1, 2, 3, or 4 units wide each; each decimal digit to be encoded consists of two bars and two spaces chosen to have a total width of 7 units...
Technology
Software development: General
null
53702
https://en.wikipedia.org/wiki/Boltzmann%20constant
Boltzmann constant
The Boltzmann constant ( or ) is the proportionality factor that relates the average relative thermal energy of particles in a gas with the thermodynamic temperature of the gas. It occurs in the definitions of the kelvin (K) and the gas constant, in Planck's law of black-body radiation and Boltzmann's entropy formula, ...
Physical sciences
Physical constants
Physics
53741
https://en.wikipedia.org/wiki/Symmetry
Symmetry
Symmetry () in everyday life refers to a sense of harmonious and beautiful proportion and balance. In mathematics, the term has a more precise definition and is usually used to refer to an object that is invariant under some transformations, such as translation, reflection, rotation, or scaling. Although these two mean...
Mathematics
Geometry
null
53759
https://en.wikipedia.org/wiki/Category%20%28mathematics%29
Category (mathematics)
In mathematics, a category (sometimes called an abstract category to distinguish it from a concrete category) is a collection of "objects" that are linked by "arrows". A category has two basic properties: the ability to compose the arrows associatively and the existence of an identity arrow for each object. A simple e...
Mathematics
Category theory
null
53776
https://en.wikipedia.org/wiki/Kruskal%27s%20algorithm
Kruskal's algorithm
Kruskal's algorithm finds a minimum spanning forest of an undirected edge-weighted graph. If the graph is connected, it finds a minimum spanning tree. It is a greedy algorithm that in each step adds to the forest the lowest-weight edge that will not form a cycle. The key steps of the algorithm are sorting and the use o...
Mathematics
Graph theory
null
53777
https://en.wikipedia.org/wiki/Ford%E2%80%93Fulkerson%20algorithm
Ford–Fulkerson algorithm
The Ford–Fulkerson method or Ford–Fulkerson algorithm (FFA) is a greedy algorithm that computes the maximum flow in a flow network. It is sometimes called a "method" instead of an "algorithm" as the approach to finding augmenting paths in a residual graph is not fully specified or it is specified in several implementat...
Mathematics
Graph theory
null
53783
https://en.wikipedia.org/wiki/Prim%27s%20algorithm
Prim's algorithm
In computer science, Prim's algorithm is a greedy algorithm that finds a minimum spanning tree for a weighted undirected graph. This means it finds a subset of the edges that forms a tree that includes every vertex, where the total weight of all the edges in the tree is minimized. The algorithm operates by building thi...
Mathematics
Graph theory
null
53784
https://en.wikipedia.org/wiki/Brute-force%20attack
Brute-force attack
In cryptography, a brute-force attack consists of an attacker submitting many passwords or passphrases with the hope of eventually guessing correctly. The attacker systematically checks all possible passwords and passphrases until the correct one is found. Alternatively, the attacker can attempt to guess the key which...
Technology
Computer security
null
53878
https://en.wikipedia.org/wiki/Betelgeuse
Betelgeuse
Betelgeuse is a red supergiant star in the constellation of Orion. It is usually the tenth-brightest star in the night sky and, after Rigel, the second-brightest in its constellation. It is a distinctly reddish, semiregular variable star whose apparent magnitude, varying between +0.0 and +1.6, has the widest range disp...
Physical sciences
Notable stars
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10949755
https://en.wikipedia.org/wiki/Scolopendridae
Scolopendridae
Scolopendridae (or, in older documents, Scolopendridæ) is a family of large centipedes (class Chilopoda). Description Nearly all species in this family have four ocelli (simple eyes) on each side of the head and only 21 pairs of legs, but there are exceptions: two scolopendrid species feature more legs (Scolopendropsi...
Biology and health sciences
Myriapoda
Animals
1566231
https://en.wikipedia.org/wiki/Tar
Tar
Tar is a dark brown or black viscous liquid of hydrocarbons and free carbon, obtained from a wide variety of organic materials through destructive distillation. Tar can be produced from coal, wood, petroleum, or peat. Mineral products resembling tar can be produced from fossil hydrocarbons, such as petroleum. Coal tar...
Physical sciences
Hydrocarbons
Chemistry
1566688
https://en.wikipedia.org/wiki/Rainbow%20lorikeet
Rainbow lorikeet
The rainbow lorikeet (Trichoglossus moluccanus) is a species of parrot found in Australia. It is common along the eastern seaboard, from northern Queensland to South Australia. Its habitat is rainforest, coastal bush and woodland areas. Six taxa traditionally listed as subspecies of the rainbow lorikeet are now treated...
Biology and health sciences
Psittaciformes
Animals
1567358
https://en.wikipedia.org/wiki/Gustnado
Gustnado
A gustnado is a brief, shallow surface-based vortex which forms within the downburst emanating from a thunderstorm. The name is a portmanteau by elision of "gust front tornado", as gustnadoes form due to non-tornadic straight-line wind features in the downdraft (outflow), specifically within the gust front of strong th...
Physical sciences
Storms
Earth science
1569600
https://en.wikipedia.org/wiki/Thermal%20expansion
Thermal expansion
Thermal expansion is the tendency of matter to increase in length, area, or volume, changing its size and density, in response to an increase in temperature (usually excluding phase transitions). Substances usually contract with decreasing temperature (thermal contraction), with rare exceptions within limited temperatu...
Physical sciences
Thermodynamics
Physics
1570772
https://en.wikipedia.org/wiki/Paleosol
Paleosol
In geoscience, paleosol (palaeosol in Great Britain and Australia) is an ancient soil that formed in the past. The definition of the term in geology and paleontology is slightly different from its use in soil science. In geology and paleontology, a paleosol is a former soil preserved by burial underneath either sedim...
Physical sciences
Sedimentology
Earth science
166681
https://en.wikipedia.org/wiki/Halibut
Halibut
Halibut is the common name for three species of flatfish in the family of right-eye flounders. In some regions, and less commonly, other species of large flatfish are also referred to as halibut. The word is derived from haly (holy) and butte (flat fish), for its popularity on Catholic holy days. Halibut are demersal ...
Biology and health sciences
Acanthomorpha
null
166689
https://en.wikipedia.org/wiki/Interferometry
Interferometry
Interferometry is a technique which uses the interference of superimposed waves to extract information. Interferometry typically uses electromagnetic waves and is an important investigative technique in the fields of astronomy, fiber optics, engineering metrology, optical metrology, oceanography, seismology, spectrosc...
Technology
Optical instruments
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166734
https://en.wikipedia.org/wiki/Altocumulus%20cloud
Altocumulus cloud
Altocumulus () is a middle-altitude cloud genus that belongs mainly to the physical category, characterized by globular masses or rolls in layers or patchesthe individual elements being larger and darker than those of cirrocumulus and smaller than those of stratocumulus. However, if the layers become tufted in appear...
Physical sciences
Clouds
Earth science
166735
https://en.wikipedia.org/wiki/Altostratus%20cloud
Altostratus cloud
Altostratus is a middle-altitude cloud genus made up of water droplets, ice crystals, or a mixture of the two. Altostratus clouds are formed when large masses of warm, moist air rise, causing water vapor to condense. Altostratus clouds are usually gray or blueish featureless sheets, although some variants have wavy or ...
Physical sciences
Clouds
Earth science
166736
https://en.wikipedia.org/wiki/Stratocumulus%20cloud
Stratocumulus cloud
}} A stratocumulus cloud, occasionally called a cumulostratus, belongs to a genus-type of clouds characterized by large dark, rounded masses, usually in groups, lines, or waves, the individual elements being larger than those in altocumulus, and the whole being at a lower height, usually below . Weak convective current...
Physical sciences
Clouds
Earth science
166737
https://en.wikipedia.org/wiki/Nimbostratus%20cloud
Nimbostratus cloud
A nimbostratus cloud is a multilevel, amorphous, nearly uniform, and often dark-grey cloud that usually produces continuous rain, snow, or sleet, but no lightning or thunder. Although it is usually a low-based stratiform cloud, it actually forms most commonly in the middle level of the troposphere and then spreads ver...
Physical sciences
Clouds
Earth science
166740
https://en.wikipedia.org/wiki/Cirrocumulus%20cloud
Cirrocumulus cloud
Cirrocumulus is one of the three main genus types of high-altitude tropospheric clouds, the other two being cirrus and cirrostratus. They usually occur at an altitude of , however they can occur as low as in the arctic and weather reporting standards such as the Canadian MANOBS suggests heights of in summer and in w...
Physical sciences
Clouds
Earth science