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4462484
https://en.wikipedia.org/wiki/Ohm
Ohm
The ohm (symbol: Ω, the uppercase Greek letter omega) is the unit of electrical resistance in the International System of Units (SI). It is named after German physicist Georg Ohm. Various empirically derived standard units for electrical resistance were developed in connection with early telegraphy practice, and the Br...
Physical sciences
Electromagnetism
null
85746
https://en.wikipedia.org/wiki/Stoma
Stoma
In botany, a stoma (: stomata, from Greek στόμα, "mouth"), also called a stomate (: stomates), is a pore found in the epidermis of leaves, stems, and other organs, that controls the rate of gas exchange between the internal air spaces of the leaf and the atmosphere. The pore is bordered by a pair of specialized parench...
Biology and health sciences
Plant: General
null
85747
https://en.wikipedia.org/wiki/Reduced%20mass
Reduced mass
In physics, reduced mass is a measure of the effective inertial mass of a system with two or more particles when the particles are interacting with each other. Reduced mass allows the two-body problem to be solved as if it were a one-body problem. Note, however, that the mass determining the gravitational force is not ...
Physical sciences
Classical mechanics
Physics
85752
https://en.wikipedia.org/wiki/Lah%20number
Lah number
In mathematics, the (signed and unsigned) Lah numbers are coefficients expressing rising factorials in terms of falling factorials and vice versa. They were discovered by Ivo Lah in 1954. Explicitly, the unsigned Lah numbers are given by the formula involving the binomial coefficient for . Unsigned Lah numbers ha...
Mathematics
Combinatorics
null
85754
https://en.wikipedia.org/wiki/Phonon
Phonon
A phonon is a collective excitation in a periodic, elastic arrangement of atoms or molecules in condensed matter, specifically in solids and some liquids. A type of quasiparticle in physics, a phonon is an excited state in the quantum mechanical quantization of the modes of vibrations for elastic structures of interact...
Physical sciences
States of matter
Physics
85816
https://en.wikipedia.org/wiki/Complete%20graph
Complete graph
In the mathematical field of graph theory, a complete graph is a simple undirected graph in which every pair of distinct vertices is connected by a unique edge. A complete digraph is a directed graph in which every pair of distinct vertices is connected by a pair of unique edges (one in each direction). Graph theory ...
Mathematics
Graph theory
null
85821
https://en.wikipedia.org/wiki/Regular%20graph
Regular graph
In graph theory, a regular graph is a graph where each vertex has the same number of neighbors; i.e. every vertex has the same degree or valency. A regular directed graph must also satisfy the stronger condition that the indegree and outdegree of each internal vertex are equal to each other. A regular graph with vertic...
Mathematics
Graph theory
null
85846
https://en.wikipedia.org/wiki/Longsword
Longsword
A longsword (also spelled as long sword or long-sword) is a type of European sword characterized as having a cruciform hilt with a grip for primarily two-handed use (around ), a straight double-edged blade of around , and weighing approximately . The "longsword" type exists in a morphological continuum with the mediev...
Technology
Swords
null
86058
https://en.wikipedia.org/wiki/Binoculars
Binoculars
Binoculars or field glasses are two refracting telescopes mounted side-by-side and aligned to point in the same direction, allowing the viewer to use both eyes (binocular vision) when viewing distant objects. Most binoculars are sized to be held using both hands, although sizes vary widely from opera glasses to large p...
Technology
Optical instruments
null
86061
https://en.wikipedia.org/wiki/Cygnus%20X-1
Cygnus X-1
Cygnus X-1 (abbreviated Cyg X-1) is a galactic X-ray source in the constellation Cygnus and was the first such source widely accepted to be a black hole. It was discovered in 1964 during a rocket flight and is one of the strongest X-ray sources detectable from Earth, producing a peak X-ray flux density of (). It remai...
Physical sciences
Other notable objects
null
86092
https://en.wikipedia.org/wiki/Bile
Bile
Bile (from Latin bilis), or gall, is a yellow-green/misty green fluid produced by the liver of most vertebrates that aids the digestion of lipids in the small intestine. In humans, bile is primarily composed of water, is produced continuously by the liver, and is stored and concentrated in the gallbladder. After a huma...
Biology and health sciences
Gastrointestinal tract
Biology
86113
https://en.wikipedia.org/wiki/Winding%20number
Winding number
In mathematics, the winding number or winding index of a closed curve in the plane around a given point is an integer representing the total number of times that the curve travels counterclockwise around the point, i.e., the curve's number of turns. For certain open plane curves, the number of turns may be a non-intege...
Mathematics
Topology
null
86333
https://en.wikipedia.org/wiki/Microbat
Microbat
Microbats constitute the suborder Microchiroptera within the order Chiroptera. Bats have long been differentiated into Megachiroptera (megabats) and Microchiroptera, based on their size, the use of echolocation by the Microchiroptera and other features; molecular evidence suggests a somewhat different subdivision, as t...
Biology and health sciences
Bats
null
86347
https://en.wikipedia.org/wiki/Group%20%28periodic%20table%29
Group (periodic table)
In chemistry, a group (also known as a family) is a column of elements in the periodic table of the chemical elements. There are 18 numbered groups in the periodic table; the 14 f-block columns, between groups 2 and 3, are not numbered. The elements in a group have similar physical or chemical characteristics of the ou...
Physical sciences
Periodic table
Chemistry
86350
https://en.wikipedia.org/wiki/Period%20%28periodic%20table%29
Period (periodic table)
A period on the periodic table is a row of chemical elements. All elements in a row have the same number of electron shells. Each next element in a period has one more proton and is less metallic than its predecessor. Arranged this way, elements in the same group (column) have similar chemical and physical properties, ...
Physical sciences
Periodic table
Chemistry
86359
https://en.wikipedia.org/wiki/Swamp
Swamp
A swamp is a forested wetland. Swamps are considered to be transition zones because both land and water play a role in creating this environment. Swamps vary in size and are located all around the world. The water of a swamp may be fresh water, brackish water, or seawater. Freshwater swamps form along large rivers or l...
Physical sciences
Wetlands
null
86367
https://en.wikipedia.org/wiki/Megabat
Megabat
Megabats constitute the family Pteropodidae of the order Chiroptera. They are also called fruit bats, Old World fruit bats, or—especially the genera Acerodon and Pteropus—flying foxes. They are the only member of the superfamily Pteropodoidea, which is one of two superfamilies in the suborder Yinpterochiroptera. Inter...
Biology and health sciences
Bats
null
86387
https://en.wikipedia.org/wiki/Vespertilionidae
Vespertilionidae
Vespertilionidae is a family of microbats, of the order Chiroptera, flying, insect-eating mammals variously described as the common, vesper, or simple nosed bats. The vespertilionid family is the most diverse and widely distributed of bat families, specialised in many forms to occupy a range of habitats and ecological ...
Biology and health sciences
Bats
Animals
86681
https://en.wikipedia.org/wiki/Tandem%20bicycle
Tandem bicycle
A tandem bicycle or twin is a bicycle (occasionally a tricycle) designed to be ridden by more than one person. The term tandem refers to the seating arrangement (fore to aft, not side by side), not the number of riders. Patents related to tandem bicycles date from the mid-1880s. Tandems can reach higher speeds than the...
Technology
Human-powered transport
null
86777
https://en.wikipedia.org/wiki/Northern%20pike
Northern pike
The northern pike (Esox lucius) is a species of carnivorous fish of the genus Esox (pikes). They are commonly found in moderately salty and fresh waters of the Northern Hemisphere (i.e. holarctic in distribution). They are known simply as a pike (: pike) in Great Britain, Ireland, most of Eastern Europe, Canada and the...
Biology and health sciences
Fishes
null
86778
https://en.wikipedia.org/wiki/Pike%20%28weapon%29
Pike (weapon)
A pike is a long thrusting spear formerly used in European warfare from the Late Middle Ages and most of the early modern period, and wielded by foot soldiers deployed in pike square formation, until it was largely replaced by bayonet-equipped muskets. The pike was particularly well known as the primary weapon of Spani...
Technology
Polearms
null
86801
https://en.wikipedia.org/wiki/Iris%20%28anatomy%29
Iris (anatomy)
The iris (: irides or irises) is a thin, annular structure in the eye in most mammals and birds that is responsible for controlling the diameter and size of the pupil, and thus the amount of light reaching the retina. In optical terms, the pupil is the eye's aperture, while the iris is the diaphragm. Eye color is defin...
Biology and health sciences
Visual system
Biology
86996
https://en.wikipedia.org/wiki/Greenhouse
Greenhouse
A greenhouse is a structure that is designed to regulate the temperature and humidity of the environment inside. There are different types of greenhouses, but they all have large areas covered with transparent materials that let sunlight pass and block it as heat. The most common materials used in modern greenhouses fo...
Technology
Buildings and infrastructure
null
87019
https://en.wikipedia.org/wiki/Ductility
Ductility
Ductility refers to the ability of a material to sustain significant plastic deformation before fracture. Plastic deformation is the permanent distortion of a material under applied stress, as opposed to elastic deformation, which is reversible upon removing the stress. Ductility is a critical mechanical performance in...
Physical sciences
Solid mechanics
Physics
87026
https://en.wikipedia.org/wiki/Tapestry
Tapestry
Tapestry is a form of textile art, traditionally woven by hand on a loom. Normally it is used to create images rather than patterns. Tapestry is relatively fragile, and difficult to make, so most historical pieces are intended to hang vertically on a wall (or sometimes in tents), or sometimes horizontally over a piece ...
Technology
Techniques_2
null
87089
https://en.wikipedia.org/wiki/Snake%20lemma
Snake lemma
The snake lemma is a tool used in mathematics, particularly homological algebra, to construct long exact sequences. The snake lemma is valid in every abelian category and is a crucial tool in homological algebra and its applications, for instance in algebraic topology. Homomorphisms constructed with its help are gener...
Mathematics
Category theory
null
87160
https://en.wikipedia.org/wiki/Haast%27s%20eagle
Haast's eagle
Haast's eagle (Hieraaetus moorei) is an extinct species of eagle that lived in the South Island of New Zealand, commonly accepted to be the of Māori mythology. It is the largest eagle known to have existed, with an estimated weight of , compared to the next-largest and extant harpy eagle (Harpia harpyja), at up to . I...
Biology and health sciences
Accipitrimorphae
Animals
87168
https://en.wikipedia.org/wiki/Arachnid
Arachnid
Arachnids are arthropods in the class Arachnida () of the subphylum Chelicerata. Arachnida includes, among others, spiders, scorpions, ticks, mites, pseudoscorpions, harvestmen, camel spiders, whip spiders and vinegaroons. Adult arachnids have eight legs attached to the cephalothorax. In some species the frontmost pa...
Biology and health sciences
Arachnids
null
87179
https://en.wikipedia.org/wiki/Closed-circuit%20television
Closed-circuit television
Closed-circuit television (CCTV), also known as video surveillance, is the use of closed-circuit television cameras to transmit a signal to a specific place on a limited set of monitors. It differs from broadcast television in that the signal is not openly transmitted, though it may employ point-to-point, point-to-mult...
Technology
Photography
null
87249
https://en.wikipedia.org/wiki/Kola%20nut
Kola nut
The kola nut (Yoruba: obi, Dagbani: guli, Hausa: goro, Igbo: ọjị, Sängö: gôro, Swahili: mukezu) is the seed of certain species of plant of the genus Cola, placed formerly in the cocoa family Sterculiaceae and now usually subsumed in the mallow family Malvaceae (as subfamily Sterculioideae). These cola species are trees...
Biology and health sciences
Nuts
Plants
87299
https://en.wikipedia.org/wiki/Heaviside%20step%20function
Heaviside step function
The Heaviside step function, or the unit step function, usually denoted by or (but sometimes , or ), is a step function named after Oliver Heaviside, the value of which is zero for negative arguments and one for positive arguments. Different conventions concerning the value are in use. It is an example of the gene...
Mathematics
Specific functions
null
87352
https://en.wikipedia.org/wiki/Graph%20of%20a%20function
Graph of a function
In mathematics, the graph of a function is the set of ordered pairs , where In the common case where and are real numbers, these pairs are Cartesian coordinates of points in a plane and often form a curve. The graphical representation of the graph of a function is also known as a plot. In the case of functions of ...
Mathematics
Basics
null
87372
https://en.wikipedia.org/wiki/Additive%20function
Additive function
In number theory, an additive function is an arithmetic function f(n) of the positive integer variable n such that whenever a and b are coprime, the function applied to the product ab is the sum of the values of the function applied to a and b: Completely additive An additive function f(n) is said to be completely ad...
Mathematics
Functions: General
null
87410
https://en.wikipedia.org/wiki/Coral%20reef
Coral reef
A coral reef is an underwater ecosystem characterized by reef-building corals. Reefs are formed of colonies of coral polyps held together by calcium carbonate. Most coral reefs are built from stony corals, whose polyps cluster in groups. Coral belongs to the class Anthozoa in the animal phylum Cnidaria, which includes...
Physical sciences
Oceanic and coastal landforms
null
87492
https://en.wikipedia.org/wiki/Oryza
Oryza
Oryza is a genus of plants in the grass family. It includes the major food crop rice (species Oryza sativa and Oryza glaberrima). Members of the genus grow as tall, wetland grasses, growing to tall; the genus includes both annual and perennial species. Oryza is situated in tribe Oryzeae, which is characterized morpho...
Biology and health sciences
Poales
Plants
87598
https://en.wikipedia.org/wiki/Date%20palm
Date palm
Phoenix dactylifera, commonly known as the date palm, is a flowering-plant species in the palm family Arecaceae, cultivated for its edible sweet fruit called dates. The species is widely cultivated across northern Africa, the Middle East, the Horn of Africa, Australia, South Asia, and California. It is naturalized in m...
Biology and health sciences
Monocots
null
87837
https://en.wikipedia.org/wiki/Ratio
Ratio
In mathematics, a ratio () shows how many times one number contains another. For example, if there are eight oranges and six lemons in a bowl of fruit, then the ratio of oranges to lemons is eight to six (that is, 8:6, which is equivalent to the ratio 4:3). Similarly, the ratio of lemons to oranges is 6:8 (or 3:4) and ...
Mathematics
Basics
null
87851
https://en.wikipedia.org/wiki/Stoat
Stoat
The stoat (Mustela erminea), also known as the Eurasian ermine or ermine, is a species of mustelid native to Eurasia and the northern regions of North America. Because of its wide circumpolar distribution, it is listed as Least Concern on the IUCN Red List. The name ermine () is used especially in its pure white winter...
Biology and health sciences
Carnivora
null
87872
https://en.wikipedia.org/wiki/Antiproton
Antiproton
The antiproton, , (pronounced p-bar) is the antiparticle of the proton. Antiprotons are stable, but they are typically short-lived, since any collision with a proton will cause both particles to be annihilated in a burst of energy. The existence of the antiproton with electric charge of , opposite to the electric char...
Physical sciences
Antimatter
Physics
87945
https://en.wikipedia.org/wiki/Terminator%20%28solar%29
Terminator (solar)
A terminator or twilight zone is a moving line that divides the daylit side and the dark night side of a planetary body. The terminator is defined as the locus of points on a planet or moon where the line through the center of its parent star is tangent. An observer on the terminator of such an orbiting body with an at...
Physical sciences
Celestial mechanics
Astronomy
88003
https://en.wikipedia.org/wiki/Menstrual%20cycle
Menstrual cycle
The menstrual cycle is a series of natural changes in hormone production and the structures of the uterus and ovaries of the female reproductive system that makes pregnancy possible. The ovarian cycle controls the production and release of eggs and the cyclic release of estrogen and progesterone. The uterine cycle gove...
Biology and health sciences
Animal reproduction
null
88042
https://en.wikipedia.org/wiki/Myopia
Myopia
Myopia, also known as near-sightedness and short-sightedness, is an eye disease where light from distant objects focuses in front of, instead of on, the retina. As a result, distant objects appear blurry while close objects appear normal. Other symptoms may include headaches and eye strain. Severe myopia is associated ...
Biology and health sciences
Disabilities
Health
88078
https://en.wikipedia.org/wiki/Prostate%20cancer
Prostate cancer
Prostate cancer is the uncontrolled growth of cells in the prostate, a gland in the male reproductive system below the bladder. Abnormal growth of prostate tissue is usually detected through screening tests, typically blood tests that check for prostate-specific antigen (PSA) levels. Those with high levels of PSA in th...
Biology and health sciences
Cancer
null
88213
https://en.wikipedia.org/wiki/Apsis
Apsis
An apsis (; ) is the farthest or nearest point in the orbit of a planetary body about its primary body. The line of apsides (also called apse line, or major axis of the orbit) is the line connecting the two extreme values. Apsides pertaining to orbits around the Sun have distinct names to differentiate themselves f...
Physical sciences
Celestial mechanics
Astronomy
88295
https://en.wikipedia.org/wiki/Golden%20eagle
Golden eagle
The golden eagle (Aquila chrysaetos) is a bird of prey living in the Northern Hemisphere. It is the most widely distributed species of eagle. Like all eagles, it belongs to the family Accipitridae. They are one of the best-known birds of prey in the Northern Hemisphere. These birds are dark brown, with lighter golden-b...
Biology and health sciences
Accipitriformes and Falconiformes
null
11442363
https://en.wikipedia.org/wiki/Boverisuchus
Boverisuchus
Boverisuchus is an extinct genus of planocraniid crocodyliforms known from the early to middle Eocene (Ypresian to Lutetian stages) of Germany and western North America. It was a relatively small crocodyliform with an estimated total length of approximately . History The type species Boverisuchus magnifrons was first...
Biology and health sciences
Prehistoric crocodiles
Animals
19048968
https://en.wikipedia.org/wiki/Spider%20web
Spider web
A spider web, spiderweb, spider's web, or cobweb (from the archaic word coppe, meaning 'spider') is a structure created by a spider out of proteinaceous spider silk extruded from its spinnerets, generally meant to catch its prey. Spider webs have existed for at least 100 million years, as witnessed in a rare find of E...
Biology and health sciences
Shelters and structures
Animals
7735022
https://en.wikipedia.org/wiki/Cage%20%28graph%20theory%29
Cage (graph theory)
In the mathematical field of graph theory, a cage is a regular graph that has as few vertices as possible for its girth. Formally, an is defined to be a graph in which each vertex has exactly neighbors, and in which the shortest cycle has a length of exactly . An is an with the smallest possible number of vertice...
Mathematics
Graph theory
null
15105978
https://en.wikipedia.org/wiki/Well
Well
A well is an excavation or structure created on the earth by digging, driving, or drilling to access liquid resources, usually water. The oldest and most common kind of well is a water well, to access groundwater in underground aquifers. The well water is drawn up by a pump, or using containers, such as buckets that a...
Technology
Food, water and health
null
16829895
https://en.wikipedia.org/wiki/Smallpox
Smallpox
Smallpox was an infectious disease caused by variola virus (often called smallpox virus), which belongs to the genus Orthopoxvirus. The last naturally occurring case was diagnosed in October 1977, and the World Health Organization (WHO) certified the global eradication of the disease in 1980, making smallpox the only ...
Biology and health sciences
Illness and injury
null
16831059
https://en.wikipedia.org/wiki/Suicide
Suicide
Suicide is the act of intentionally causing one's own death. Mental disorders, physical disorders, and substance abuse are common risk factors. Some suicides are impulsive acts driven by stress (such as from financial or academic difficulties), relationship problems (such as breakups or divorces), or harassment and bu...
Biology and health sciences
Biology
null
3290705
https://en.wikipedia.org/wiki/Twelvefold%20way
Twelvefold way
In combinatorics, the twelvefold way is a systematic classification of 12 related enumerative problems concerning two finite sets, which include the classical problems of counting permutations, combinations, multisets, and partitions either of a set or of a number. The idea of the classification is credited to Gian-Car...
Mathematics
Combinatorics
null
3291706
https://en.wikipedia.org/wiki/Motor%20ship
Motor ship
A motor ship or motor vessel is a ship propelled by an internal combustion engine, usually a diesel engine. The names of motor ships are often prefixed with MS, M/S, MV or M/V. Engines for motorships were developed during the 1890s, and by the early 20th century, motorships began to cross the waters. History The firs...
Technology
Naval transport
null
3292675
https://en.wikipedia.org/wiki/Reservoir
Reservoir
A reservoir (; ) is an enlarged lake behind a dam, usually built to store fresh water, often doubling for hydroelectric power generation. Reservoirs are created by controlling a watercourse that drains an existing body of water, interrupting a watercourse to form an embayment within it, excavating, or building any n...
Technology
Hydraulic infrastructure
null
3293019
https://en.wikipedia.org/wiki/Cecidomyiidae
Cecidomyiidae
Cecidomyiidae is a family of flies known as gall midges or gall gnats. As the name implies, the larvae of most gall midges feed within plant tissue, creating abnormal plant growths called galls. Cecidomyiidae are very fragile small insects usually only in length; many are less than long. They are characterised by hai...
Biology and health sciences
Flies (Diptera)
Animals
12395897
https://en.wikipedia.org/wiki/Alligator%20pepper
Alligator pepper
Alligator pepper (also known as Ata Ire or Ose Oji or mbongo spice or hepper pepper) is a West African spice made from the seeds and seed pods of Aframomum danielli, A. citratum or A. exscapum. It is a close relative of grains obtained from the closely related species, Aframomum melegueta or "grains of paradise". Unlik...
Biology and health sciences
Herbs and spices
Plants
1129026
https://en.wikipedia.org/wiki/Hyperon
Hyperon
In particle physics, a hyperon is any baryon containing one or more strange quarks, but no charm, bottom, or top quarks. This form of matter may exist in a stable form within the core of some neutron stars. Hyperons are sometimes generically represented by the symbol Y. History and research The first research into hy...
Physical sciences
Fermions
Physics
1129074
https://en.wikipedia.org/wiki/Grand%20canonical%20ensemble
Grand canonical ensemble
In statistical mechanics, the grand canonical ensemble (also known as the macrocanonical ensemble) is the statistical ensemble that is used to represent the possible states of a mechanical system of particles that are in thermodynamic equilibrium (thermal and chemical) with a reservoir. The system is said to be open in...
Physical sciences
Statistical mechanics
Physics
1129256
https://en.wikipedia.org/wiki/Cupressus%20sempervirens
Cupressus sempervirens
Cupressus sempervirens, the Mediterranean cypress (also known as Italian cypress, Tuscan cypress, Persian cypress, or pencil pine), is a species of cypress native to the eastern Mediterranean region and Iran. While some studies show it has modern medicinal properties, it is most noted for uses in folk medicine, where t...
Biology and health sciences
Cupressaceae
Plants
1129919
https://en.wikipedia.org/wiki/Metallicity
Metallicity
In astronomy, metallicity is the abundance of elements present in an object that are heavier than hydrogen and helium. Most of the normal currently detectable (i.e. non-dark) matter in the universe is either hydrogen or helium, and astronomers use the word "metals" as convenient shorthand for "all elements except hydro...
Physical sciences
Stellar astronomy
null
1130627
https://en.wikipedia.org/wiki/Hyaline%20cartilage
Hyaline cartilage
Hyaline cartilage is the glass-like (hyaline) and translucent cartilage found on many joint surfaces. It is also most commonly found in the ribs, nose, larynx, and trachea. Hyaline cartilage is pearl-gray in color, with a firm consistency and has a considerable amount of collagen. It contains no nerves or blood vessels...
Biology and health sciences
Tissues
Biology
1131010
https://en.wikipedia.org/wiki/Hylidae
Hylidae
Hylidae is a wide-ranging family of frogs commonly referred to as "tree frogs and their allies". However, the hylids include a diversity of frog species, many of which do not live in trees, but are terrestrial or semiaquatic. Taxonomy and systematics The earliest known fossils that can be assigned to this family are f...
Biology and health sciences
Amphibians
null
1131045
https://en.wikipedia.org/wiki/Barbary%20lion
Barbary lion
The Barbary lion was a population of the lion subspecies Panthera leo leo. It was also called North African lion, Atlas lion and Egyptian lion. It lived in the mountains and deserts of the Maghreb of North Africa from Morocco to Egypt. It was eradicated following the spread of firearms and bounties for shooting lions. ...
Biology and health sciences
Felines
Animals
1131151
https://en.wikipedia.org/wiki/Heliosphere
Heliosphere
The heliosphere is the magnetosphere, astrosphere, and outermost atmospheric layer of the Sun. It takes the shape of a vast, tailed bubble-like region of space. In plasma physics terms, it is the cavity formed by the Sun in the surrounding interstellar medium. The "bubble" of the heliosphere is continuously "inflated" ...
Physical sciences
Solar System
Astronomy
1131927
https://en.wikipedia.org/wiki/Greywacke
Greywacke
Greywacke or graywacke (German grauwacke, signifying a grey, earthy rock) is a variety of sandstone generally characterized by its hardness (6–7 on Mohs scale), dark color, and poorly sorted angular grains of quartz, feldspar, and small rock fragments or sand-size lithic fragments set in a compact, clay-fine matrix. It...
Physical sciences
Sedimentary rocks
Earth science
1132756
https://en.wikipedia.org/wiki/Animal%20locomotion
Animal locomotion
In ethology, animal locomotion is any of a variety of methods that animals use to move from one place to another. Some modes of locomotion are (initially) self-propelled, e.g., running, swimming, jumping, flying, hopping, soaring and gliding. There are also many animal species that depend on their environment for trans...
Biology and health sciences
Ethology
null
2403422
https://en.wikipedia.org/wiki/Lightheadedness
Lightheadedness
Lightheadedness is a common and typically unpleasant sensation of dizziness or a feeling that one may faint. The sensation of lightheadedness can be short-lived, prolonged, or, rarely, recurring. In addition to dizziness, the individual may feel as though their head is weightless. The individual may also feel as though...
Biology and health sciences
Symptoms and signs
Health
2403771
https://en.wikipedia.org/wiki/Oakmoss
Oakmoss
Oakmoss (scientific name Evernia prunastri) is a species of lichen. It can be found in many mountainous temperate forests throughout the Northern Hemisphere. Oakmoss grows primarily on the trunk and branches of oak trees, but is also commonly found on the bark of other deciduous trees and conifers such as fir and pine....
Biology and health sciences
Lichens
Plants
4465266
https://en.wikipedia.org/wiki/Hesperocyparis%20lusitanica
Hesperocyparis lusitanica
Hesperocyparis lusitanica, the Mexican cypress, cedar-of-Goa or Goa cedar, is a species of cypress native to Mexico and Central America (Guatemala, El Salvador and Honduras). It has also been introduced to Belize, Costa Rica and Nicaragua, growing at altitude. The scientific name lusitanica (of Portugal) refers to it...
Biology and health sciences
Cupressaceae
Plants
4467052
https://en.wikipedia.org/wiki/Bothriolepis
Bothriolepis
Bothriolepis (from , 'trench' and 'scale') was a widespread, abundant and diverse genus of antiarch placoderms that lived during the Middle to Late Devonian period of the Paleozoic Era. Historically, Bothriolepis resided in an array of paleo-environments spread across every paleocontinent, including near shore mari...
Biology and health sciences
Prehistoric fish
Animals
10005756
https://en.wikipedia.org/wiki/Sample%20mean%20and%20covariance
Sample mean and covariance
The sample mean (sample average) or empirical mean (empirical average), and the sample covariance or empirical covariance are statistics computed from a sample of data on one or more random variables. The sample mean is the average value (or mean value) of a sample of numbers taken from a larger population of numbers,...
Mathematics
Statistics
null
10006190
https://en.wikipedia.org/wiki/Bus%20garage
Bus garage
A bus garage, also known as a bus depot, bus base or bus barn, is a facility where buses are stored and maintained. In many conurbations, bus garages are on the site of former car barns or tram sheds, where trams (streetcars) were stored, and the operation transferred to buses. In other areas, garages were built to rep...
Technology
Concepts of ground transport
null
1722009
https://en.wikipedia.org/wiki/Paranthropus%20aethiopicus
Paranthropus aethiopicus
Paranthropus aethiopicus is an extinct species of robust australopithecine from the Late Pliocene to Early Pleistocene of East Africa about 2.7–2.3 million years ago. However, it is much debated whether or not Paranthropus is an invalid grouping and is synonymous with Australopithecus, so the species is also often clas...
Biology and health sciences
Australopithecines
Biology
1722616
https://en.wikipedia.org/wiki/Physical%20object
Physical object
In natural language and physical science, a physical object or material object (or simply an object or body) is a contiguous collection of matter, within a defined boundary (or surface), that exists in space and time. Usually contrasted with abstract objects and mental objects. Also in common usage, an object is not c...
Physical sciences
Physics basics: General
Physics
1722958
https://en.wikipedia.org/wiki/Diammonium%20phosphate
Diammonium phosphate
Diammonium phosphate (DAP; IUPAC name diammonium hydrogen phosphate; chemical formula (NH4)2(HPO4)) is one of a series of water-soluble ammonium phosphate salts that can be produced when ammonia reacts with phosphoric acid. Solid diammonium phosphate shows a dissociation pressure of ammonia as given by the following ...
Physical sciences
Phosphoric oxyanions
Chemistry
406624
https://en.wikipedia.org/wiki/Time%20series
Time series
In mathematics, a time series is a series of data points indexed (or listed or graphed) in time order. Most commonly, a time series is a sequence taken at successive equally spaced points in time. Thus it is a sequence of discrete-time data. Examples of time series are heights of ocean tides, counts of sunspots, and t...
Mathematics
Statistics
null
406902
https://en.wikipedia.org/wiki/Geometrized%20unit%20system
Geometrized unit system
A geometrized unit system or geometrodynamic unit system is a system of natural units in which the base physical units are chosen so that the speed of light in vacuum, c, and the gravitational constant, G, are set equal to unity. The geometrized unit system is not a completely defined system. Some systems are geometri...
Physical sciences
Measurement systems
Basics and measurement
407233
https://en.wikipedia.org/wiki/Global%20dimming
Global dimming
Global dimming is a decline in the amount of sunlight reaching the Earth's surface. It is caused by atmospheric particulate matter, predominantly sulfate aerosols, which are components of air pollution. Global dimming was observed soon after the first systematic measurements of solar irradiance began in the 1950s. This...
Physical sciences
Climate change
Earth science
407615
https://en.wikipedia.org/wiki/Sodium%20nitrite
Sodium nitrite
Sodium nitrite is an inorganic compound with the chemical formula . It is a white to slightly yellowish crystalline powder that is very soluble in water and is hygroscopic. From an industrial perspective, it is the most important nitrite salt. It is a precursor to a variety of organic compounds, such as pharmaceuticals...
Physical sciences
Nitric oxyanions
Chemistry
407822
https://en.wikipedia.org/wiki/Grouper
Grouper
Groupers are fish of any of a number of genera in the subfamily Epinephelinae of the family Serranidae, in the order Perciformes. Not all serranids are called "groupers"; the family also includes the sea basses. The common name "grouper" is usually given to fish in one of two large genera: Epinephelus and Mycteroperca...
Biology and health sciences
Acanthomorpha
null
407852
https://en.wikipedia.org/wiki/Hyacinth
Hyacinth
Hyacinthus is a small genus of bulbous herbs, spring-blooming perennials. They are fragrant flowering plants in the family Asparagaceae, subfamily Scilloideae and are commonly called hyacinths (). The genus is native predominantly to the Eastern Mediterranean region from the south of Turkey to Northern Israel, althoug...
Biology and health sciences
Asparagales
Plants
408026
https://en.wikipedia.org/wiki/Relativistic%20Doppler%20effect
Relativistic Doppler effect
The relativistic Doppler effect is the change in frequency, wavelength and amplitude of light, caused by the relative motion of the source and the observer (as in the classical Doppler effect, first proposed by Christian Doppler in 1842), when taking into account effects described by the special theory of relativity. ...
Physical sciences
Waves
Physics
408169
https://en.wikipedia.org/wiki/Eastern%20gray%20squirrel
Eastern gray squirrel
The eastern gray squirrel (Sciurus carolinensis), also known, particularly outside of the United States, as simply the grey squirrel, is a tree squirrel in the genus Sciurus. It is native to eastern North America, where it is the most prodigious and ecologically essential natural forest regenerator. Widely introduced t...
Biology and health sciences
Rodents
Animals
408195
https://en.wikipedia.org/wiki/Cauchy%20principal%20value
Cauchy principal value
In mathematics, the Cauchy principal value, named after Augustin-Louis Cauchy, is a method for assigning values to certain improper integrals which would otherwise be undefined. In this method, a singularity on an integral interval is avoided by limiting the integral interval to the non singular domain. Formulation De...
Mathematics
Complex analysis
null
408201
https://en.wikipedia.org/wiki/Sieve
Sieve
A sieve, fine mesh strainer, or sift, is a tool used for separating wanted elements from unwanted material or for controlling the particle size distribution of a sample, using a screen such as a woven mesh or net or perforated sheet material. The word sift derives from sieve. In cooking, a sifter is used to separate a...
Technology
Flexible components
null
408239
https://en.wikipedia.org/wiki/Tracer%20ammunition
Tracer ammunition
Tracer ammunition, or tracers, are bullets or cannon-caliber projectiles that are built with a small pyrotechnic charge in their base. When fired, the pyrotechnic composition is ignited by the burning powder and burns very brightly, making the projectile trajectory visible to the naked eye during daylight, and very bri...
Technology
Ammunition
null
408703
https://en.wikipedia.org/wiki/Intercropping
Intercropping
Intercropping is a multiple cropping practice that involves the cultivation of two or more crops simultaneously on the same field, a form of polyculture. The most common goal of intercropping is to produce a greater yield on a given piece of land by making use of resources or ecological processes that would otherwise n...
Technology
Agriculture_2
null
409255
https://en.wikipedia.org/wiki/Green%20manure
Green manure
In agriculture, a green manure is a crop specifically cultivated to be incorporated into the soil while still green. Typically, the green manure's biomass is incorporated with a plow or disk, as is often done with (brown) manure. The primary goal is to add organic matter to the soil for its benefits. Green manuring is...
Technology
Agronomical techniques
null
210481
https://en.wikipedia.org/wiki/Gull
Gull
Gulls, or colloquially seagulls, are seabirds of the subfamily Larinae. They are most closely related to terns and skimmers, distantly related to auks, and even more distantly related to waders. Until the 21st century, most gulls were placed in the genus Larus, but that arrangement is now considered polyphyletic, leadi...
Biology and health sciences
Charadriiformes
null
210533
https://en.wikipedia.org/wiki/Nymph%20%28biology%29
Nymph (biology)
In biology, a nymph (from Ancient Greek νύμφα nūmphē meaning "bride") is the juvenile form of some invertebrates, particularly insects, which undergoes gradual metamorphosis (hemimetabolism) before reaching its adult stage. Unlike a typical larva, a nymph's overall form already resembles that of the adult, except for ...
Biology and health sciences
Animal ontogeny
null
210555
https://en.wikipedia.org/wiki/Waste%20management
Waste management
Waste management or waste disposal includes the processes and actions required to manage waste from its inception to its final disposal. This includes the collection, transport, treatment, and disposal of waste, together with monitoring and regulation of the waste management process and waste-related laws, technologies...
Technology
Basics_6
null
210596
https://en.wikipedia.org/wiki/Irritable%20bowel%20syndrome
Irritable bowel syndrome
Irritable bowel syndrome (IBS) is a functional gastrointestinal disorder characterized by a group of symptoms that commonly include abdominal pain, abdominal bloating and changes in the consistency of bowel movements. These symptoms may occur over a long time, sometimes for years. IBS can negatively affect quality of l...
Biology and health sciences
Specific diseases
Health
210648
https://en.wikipedia.org/wiki/Declarative%20programming
Declarative programming
In computer science, declarative programming is a programming paradigm—a style of building the structure and elements of computer programs—that expresses the logic of a computation without describing its control flow. Many languages that apply this style attempt to minimize or eliminate side effects by describing wha...
Technology
Software development: General
null
210755
https://en.wikipedia.org/wiki/Hydrogen%20chloride
Hydrogen chloride
The compound hydrogen chloride has the chemical formula and as such is a hydrogen halide. At room temperature, it is a colorless gas, which forms white fumes of hydrochloric acid upon contact with atmospheric water vapor. Hydrogen chloride gas and hydrochloric acid are important in technology and industry. Hydrochlori...
Physical sciences
Hydrogen compounds
Chemistry
210782
https://en.wikipedia.org/wiki/Tern
Tern
Terns are seabirds in the family Laridae, subfamily Sterninae, that have a worldwide distribution and are normally found near the sea, rivers, or wetlands. Terns are treated in eleven genera in a subgroup of the family Laridae, which also includes several genera of gulls and the skimmers (Rynchops). They are slender, l...
Biology and health sciences
Charadriiformes
null
210792
https://en.wikipedia.org/wiki/Skua
Skua
The skuas are a group of predatory seabirds with seven species forming the genus Stercorarius, the only genus in the family Stercorariidae. The three smaller skuas, the Arctic skua, the long-tailed skua, and the pomarine skua, are called jaegers in North American English. The English word "skua" comes from the Faroes...
Biology and health sciences
Charadriiformes
Animals
210799
https://en.wikipedia.org/wiki/Sunbittern
Sunbittern
The sunbittern (Eurypyga helias) is a bittern-like bird of tropical regions of the Americas, and the sole member of the family Eurypygidae (sometimes spelled Eurypigidae) and genus Eurypyga. It is found in Central and South America, and has three subspecies. The sunbittern shows both morphological and molecular similar...
Biology and health sciences
Basics
Animals
210820
https://en.wikipedia.org/wiki/Phasianidae
Phasianidae
The Phasianidae are a family of heavy, ground-living birds, which includes pheasants, partridges, junglefowl, chickens, turkeys, Old World quail, and peafowl. The family includes many of the most popular gamebirds. The family includes 185 species divided into 54 genera. It was formerly broken up into two subfamilies, t...
Biology and health sciences
Galliformes
Animals
210845
https://en.wikipedia.org/wiki/Woodpecker
Woodpecker
Woodpeckers are part of the bird family Picidae, which also includes the piculets, wrynecks and sapsuckers. Members of this family are found worldwide, except for Australia, New Guinea, New Zealand, Madagascar and the extreme polar regions. Most species live in forests or woodland habitats, although a few species are k...
Biology and health sciences
Piciformes
null
210880
https://en.wikipedia.org/wiki/Crater%20%28constellation%29
Crater (constellation)
Crater is a small constellation in the southern celestial hemisphere. Its name is the latinization of the Greek krater, a type of cup used to water down wine. One of the 48 constellations listed by the second-century astronomer Ptolemy, it depicts a cup that has been associated with the god Apollo and is perched on the...
Physical sciences
Other
Astronomy