20-letter words containing c, o, t, r, a
- arches national park — a national park in E Utah: natural arch formations. 114 sq. mi. (295 sq. km).
- architectural bronze — a brass alloy of about 57 percent copper, 41 percent zinc, and 2 percent lead.
- aristarchus of samos — 3rd century bc, Greek astronomer who anticipated Copernicus in advancing the theory that the earth revolves around the sun
- articulatory feature — a property of a speech sound based on its voicing or on its place or manner of articulation in the vocal tract, as voiceless, bilabial, or stop used in describing the sound (p).
- artificial harmonics — harmonics of a note produced on a stringed instrument by lightly touching a stopped sounded string.
- artificial selection — a process in the breeding of animals and in the cultivation of plants by which the breeder chooses to perpetuate only those forms having certain desirable inheritable characteristics.
- asexual reproduction — reproduction, as budding, fission, or spore formation, not involving the union of gametes.
- assessment procedure — an established method of assessing students or workers
- association of stars — a sparsely populated group of between 10 and 1000 young stars of similar spectral type and common origin that are moving too fast to form a permanent, gravitationally bound system.
- astatic galvanometer — a galvanometer that is unaffected by the earth's magnetic field and is used for measuring small currents.
- at someone's service — ready to serve or cooperate with someone
- at the crack of dawn — If you say that someone does something at the crack of dawn, you are emphasizing that they do it very early in the morning.
- at two hours' notice — with notification only two hours in advance
- atmospheric pressure — Atmospheric pressure is the pressure of the atmosphere on the Earth's surface.
- attic salt (or wit) — graceful, piercing wit
- automobile insurance — Automobile insurance is insurance coverage for cars.
- axiomatic set theory — (theory) One of several approaches to set theory, consisting of a formal language for talking about sets and a collection of axioms describing how they behave. There are many different axiomatisations for set theory. Each takes a slightly different approach to the problem of finding a theory that captures as much as possible of the intuitive idea of what a set is, while avoiding the paradoxes that result from accepting all of it, the most famous being Russell's paradox. The main source of trouble in naive set theory is the idea that you can specify a set by saying whether each object in the universe is in the "set" or not. Accordingly, the most important differences between different axiomatisations of set theory concern the restrictions they place on this idea (known as "comprehension"). NBG (von Neumann-Bernays-Goedel) set theory sort of allows comprehension for all formulae without restriction, but distinguishes between two kinds of set, so that the sets produced by applying comprehension are only second-class sets. NBG is exactly as powerful as ZF, in the sense that any statement that can be formalised in both theories is a theorem of ZF if and only if it is a theorem of ZFC. MK (Morse-Kelley) set theory is a strengthened version of NBG, with a simpler axiom system. It is strictly stronger than NBG, and it is possible that NBG might be consistent but MK inconsistent. ML ("Modern Logic") is to NF as NBG is to ZF. (Its name derives from the title of the book in which Quine introduced an early, defective, form of it). It is stronger than ZF (it can prove things that ZF can't), but if NF is consistent then ML is too.
- baccalaureate sermon — a farewell sermon addressed to a graduating class in some U.S. colleges and schools.
- back the wrong horse — to bet on a horse that loses the race
- background radiation — low-intensity radiation from, for example, small amounts of radioisotopes in soil, air, building materials, etc
- backwards compatible — backward compatibility
- bacteriochlorophylls — Plural form of bacteriochlorophyll.
- ballistic trajectory — the path of an unpowered object, as a missile, moving only under the influence of gravity and possibly atmospheric friction and with its surface providing no significant lift to alter the course of flight.
- basal metabolic rate — the rate at which heat is produced by the body at rest, 12 to 14 hours after eating, measured in kilocalories per square metre of body surface per hour
- basic lead carbonate — ceruse.
- basic object adapter — (architecture) (BOA) Part of the CORBA architecture.
- bats-wing coral-tree — a small tree, Erythrina verspertilio, of tropical and subtropical Australia with red flowers and leaves shaped like the wings of a bat
- be called to the bar — to become a barrister
- biological diversity — Biological diversity is the same as biodiversity.
- black-throated diver — a diving bird, Gavia arctica, found in Europe and Asia, and a rare summer visitor to the UK
- blue screen of death — (humour) (BSOD) The infamous white-on-blue text screen which appears when Microsoft Windows crashes. BSOD is mostly seen on the 16-bit systems such as Windows 3.1, but also on Windows 95 and apparently even under Windows NT 4. It is most likely to be caused by a GPF, although Windows 95 can do it if you've removed a required CD-ROM from the drive. It is often impossible to recover cleanly from a BSOD. The acronym BSOD is sometimes used as a verb, e.g. "Windoze just keeps BSODing on me today".
- bolometric magnitude — the magnitude of a star derived either from the total energy that it radiates at all wavelengths or from the total energy of those of its wavelengths that are received on earth.
- born-again christian — person: evangelical
- boulogne billancourt — a suburb of Paris, in N France.
- boulogne-billancourt — an industrial suburb of SW Paris. Pop: 106 367 (1999)
- bring home the bacon — If you bring home the bacon, you achieve what you needed to achieve.
- broadcast journalism — journalism as practiced in radio and television.
- broadcasting station — a television or radio station
- buck's horn plantain — a Eurasian plant, Plantago coronopus, having leaves resembling a buck's horn: family Plantaginaceae
- buoyancy compensator — an inflatable vest used to control one's buoyancy underwater or to rest at the surface, usually having a connecting hose for inflation or deflation by mouth and a CO 2 cartridge for rapid, emergency inflation.
- bureau of the census — the division of the Department of Commerce that gathers, tabulates, and correlates census statistics.
- by their own account — If you say that something concerning a particular person is true by his or her own account, you mean that you believe it because that person has said it is true.
- by/from all accounts — If you say that something is true by all accounts or from all accounts, you believe it is true because other people say so.
- caesar and cleopatra — a comedy (1898) by G. B. Shaw.
- calcium hypochlorite — a white, crystalline compound, Ca(OCl) 2 , used as a disinfectant and bleaching agent.
- cancel a reservation — If you cancel a reservation, you stop it because someone who has booked a room has informed you that they no longer wish to stay there.
- canine leptospirosis — an often fatal intestinal disease in dogs, caused by any of several spirochetes of the genus Leptospira.
- cantabrian mountains — a mountain chain along the N coast of Spain, consisting of a series of high ridges that rise over 2400 m (8000 ft): rich in minerals (esp coal and iron)
- capacitive crosstalk — Capacitive crosstalk is a situation in which a signal on one line can cause a smaller version of the same signal on an adjacent line because of the capacitance between the lines.
- capillary attraction — a force that is the resultant of adhesion, cohesion, and surface tension in liquids which are in contact with solids, as in a capillary tube: when the cohesive force is greater, the surface of the liquid tends to rise in the tube, as with mercury; when the adhesive force is greater, the surface tends to be depressed, as with water