18-letter words containing m, a, t, r
- assignment problem — (mathematics, algorithm) (Or "linear assignment") Any problem involving minimising the sum of C(a, b) over a set P of pairs (a, b) where a is an element of some set A and b is an element of set B, and C is some function, under constraints such as "each element of A must appear exactly once in P" or similarly for B, or both. For example, the a's could be workers and the b's projects. The problem is "linear" because the "cost function" C() depends only on the particular pairing (a, b) and is independent of all other pairings.
- associative memory — content addressable memory
- assortative mating — the reproductive pairing of individuals that have more traits in common than would likely be the case if mating were random (contrasted with disassortative mating).
- assumption of risk — Assumption of risk is the practice of paying for minor losses yourself, but protecting against catastrophic losses by buying insurance cover.
- ast computers, llc — (company) The private company formed in January 1999 when Mr. Beny Alagem, the former chairman of Packard Bell NEC, Inc., bought the name and intellectual property of AST Research, Inc.. AST Computers, LLC provide hardware, software, and services for small US businesses. Address: Los Angeles, CA, USA.
- astrometric binary — a binary star that can be recognized as such because of its undulating proper motion.
- astronomical clock — a complex clock showing astronomical phenomena, such as the phases of the moon
- asymmetric warfare — warfare in which opposing groups or nations have unequal military resources, and the weaker opponent uses unconventional weapons and tactics, as terrorism, to exploit the vulnerabilities of the enemy.
- asymptotic freedom — a property of the force between quarks, according to quantum chromodynamics, such that they behave almost like free particles when they are close together within a hadron.
- at boardroom level — among directors
- at/from a distance — If you are at a distance from something, or if you see it or remember it from a distance, you are a long way away from it in space or time.
- atmospheric engine — an early form of single-acting engine in which the power stroke is provided by atmospheric pressure acting upon a piston in an exhausted cylinder.
- atmospheric window — wavelengths of the electromagnetic spectrum that can be transmitted through the earth's atmosphere. Atmospheric windows occur in the visible, infrared, and radio regions of the spectrum
- augmented interval — an interval that is a half step greater than the corresponding major or perfect interval
- automatic exposure — the automatic adjustment of the lens aperture and shutter speed of a camera by a control mechanism
- automatic tracking — a radar tracking system in which an automatic device uses the echo signal from the tracked object to keep the radar constantly beamed on target and to compute the range of the object.
- bachelor apartment — a flat consisting of one room that is used as a sitting room and bedroom, as well as a kitchenette and a bathroom
- ballistocardiogram — a tracing made by a ballistocardiograph
- barium thiosulfate — a white, crystalline, water-insoluble, poisonous solid, BaS 2 O 3 ⋅H 2 O, used chiefly in the manufacture of explosives, matches, paints, and varnishes.
- basal conglomerate — a conglomerate deposited on an erosion surface and constituting the bottom layer of a stratigraphic series.
- basement apartment — an apartment below the ground floor of a building
- battery eliminator — eliminator (def 2).
- battery-eliminator — a person or thing that eliminates.
- battle of omdurman — a battle (1898) in which the Mahdi's successor and his Ansar followers were defeated by Lord Kitchener's British forces
- beefsteak mushroom — an edible bracket fungus, Fistulina hepatica, that grows on trees and can rot the heartwood of living oaks and chestnuts.
- benchmark position — a public service job used for comparison with a similar position, such as a position in commerce, for wage settlements
- bernard montgomery — Bernard Law, 1st Viscount Montgomery of Alamein ("Monty") 1887–1976, British field marshal: World War II commander of British 8th Army in Africa and Europe.
- bernard of menthon — Saint(11th cent.); Fr. monk who founded hospices in the Swiss Alps: his day is May 28
- best-ball foursome — a match, scored by holes, between two pairs of players, in which the score of the lower scoring member of each pair is taken as their score for the hole.
- bichromate process — any of several methods of photography in which the light-sensitive medium is alkaline bichromate associated with a colloid such as gum, albumen, or gelatin.
- bilateral symmetry — the property of an organism or part of an organism such that, if cut in only one plane, the two cut halves are mirror images of each other
- bioinstrumentation — the use of instruments, as sensors, to detect and measure certain body functions, as of persons in spaceflight, and transmit the data to a point where it is evaluated
- black lives matter — a political and social movement originating among African Americans, emphasizing basic human rights and racial equality for black people and campaigning against various forms of racism. Abbreviations: BLM, B.L.M.
- bottom dead center — Bottom dead center is the point at which the piston of an engine is nearest to the axis of the crankshaft. On a vertical engine, this is the lowest point that the piston reaches.
- bottom dead centre — the position of the crank of a reciprocating engine when the piston is at its nearest point to the crankshaft
- bounty-fed farmers — farmers who benefit from subsidies
- brand-name product — A brand-name product is one which is made by a well-known manufacturer and has the manufacturer's label on it.
- breast enhancement — a surgical procedure to increase the size of a woman's breasts
- breast enlargement — a surgical procedure to increase the size of a woman's breasts
- british somaliland — a former British protectorate (1884–1960) in E Africa, on the Gulf of Aden: united with Italian Somaliland in 1960 to form Somalia (or the Somali Republic); in 1991 the self-styled republic of Somaliland, covering the same area as the former British Somaliland, declared itself independent and continues to function largely as a separate entity, though without international recognition
- bromochloromethane — chlorobromomethane.
- brothers karamazov — a novel (1880) by Dostoevsky.
- building materials — materials such as bricks, cement, timber, etc
- burkitt's lymphoma — a cancer characterized by tumors containing lymphoid cells, occurring esp. in children, in the jaw, eyes, and internal organs: it is associated with the Epstein-Barr virus
- burst at the seams — to break, break open, or fly apart with sudden violence: The bitter cold caused the pipes to burst.
- butter-and-egg man — a prosperous businessman from a small town or a farmer who spends his money ostentatiously on visits to a big city.
- cabinet government — parliamentary government.
- calcium propionate — a white, water-soluble powder, CaC 6 H 10 O 4 , used in bakery products to inhibit the growth of fungi.
- cambrian mountains — a mountain range in Wales, extending from Carmarthenshire in the S to Denbighshire in the N. Highest peak: Aran Fawddwy, 891 m (2970 ft)
- camembert (cheese) — a soft, rich, creamy partly ripened cheese