20-letter words containing a, e, l, u, r
- operational calculus — a method for solving a differential equation by treating differential operators as ordinary algebraic quantities, thus obtaining a simpler problem.
- oscillating universe — a variant model of the closed universe in which the universe undergoes cycles of expansion and contraction.
- ousterhout's fallacy — Ousterhout's dichotomy
- over-intellectualize — to seek or consider the rational content or form of.
- overenthusiastically — With excessive enthusiasm.
- pale western cutworm — the larva of a noctuid moth, Agrotis orthogonia, of the western U.S. and Canada, that seriously damages grains, beets, potatoes, alfalfa, etc., by feeding underground on roots and stems.
- paper qualifications — qualifications gained through official examinations, etc, rather than through experience
- pappus of alexandria — 3rd century bc, Greek mathematician, whose eight-volume Synagoge is a valuable source of information about Greek mathematics
- parallel of altitude — almucantar.
- parallel of latitude — parallel (def 9).
- parametric equalizer — an electronic device for cutting or boosting selected frequencies by continuous narrowing or widening of the frequencies to be filtered
- particulate scrubber — A particulate scrubber is a scrubber in which a liquid is mixed with the gas to collect solids.
- peculiar institution — black slavery in the southern U.S. before the Civil War.
- pedal steel (guitar) — a steel guitar mounted on legs and equipped with pedals that serve as an additional means of changing pitch
- pedro juan caballero — a city in E central Paraguay.
- pentobarbital sodium — a barbiturate drug used in medicine as a sedative and hypnotic. Formula: C11H17N2O3Na
- permonosulfuric acid — persulfuric acid (def 1).
- peroxysulphuric acid — a white hygroscopic crystalline unstable oxidizing acid. Formula: H2SO5
- perpendicular gothic — the style of Gothic architecture in England during the 14th and 15th centuries, characterized by tracery having vertical lines, a four-centred arch, and fan vaulting
- physical double star — two stars that appear as one if not viewed through a telescope with adequate magnification, such as two stars that are separated by a great distance but are nearly in line with each other and an observer (optical double star) or those that are relatively close together and comprise a single physical system (physical double star)
- pipeline burst cache — (hardware, storage) (PB Cache) A synchronous cache built from pipelined SRAM. A cache in which reading or writing a new location takes multiple cycles but subsequent locations can be accessed in a single cycle. On Pentium systems in 1996, pipeline burst caches are frequently used as secondary caches. The first 8 bytes of data are transferred in 3 CPU cycles, and the next 3 8-byte pieces of data are transferred in one cycle each.
- population inversion — a condition of matter in which more electrons are in a high energy state than in a lower energy state, as is required for the operation of a laser.
- population parameter — a quantity or statistical measure that, for a given population, is fixed and that is used as the value of a variable in some general distribution or frequency function to make it descriptive of that population: The mean and variance of a population are population parameters.
- prefecture apostolic — a territory in the early stage of missionary development.
- premenstrual tension — Premenstrual tension is the same as premenstrual syndrome. The abbreviation PMT is often used.
- prenuptial agreement — A prenuptial agreement is a written contract made between a man and a woman before they marry, in which they state how their assets such as property and money should be divided if they get divorced.
- prepatellar bursitis — inflammation and swelling of the bursa in front of the kneecap, caused esp by constant kneeling on a hard surface
- prince william sound — a sound in the Gulf of Alaska, on the S coast of Alaska: S end of Trans-Alaska oil pipeline at port of Valdez.
- procedural agreement — regulations agreed between the parties to collective bargaining, defining the bargaining units, bargaining scope, procedures for collective bargaining, and the facilities to be provided to trade union representatives
- programming language — a high-level language used to write computer programs, as COBOL or BASIC, or, sometimes, an assembly language.
- property speculation — the buying or selling of property in the hope of deriving capital gains
- proportional counter — a radiation counter in which the strength of each electric pulse generated per count is proportional to the energy of the particle or photon producing the pulse, alpha particles producing a different electric pulse from beta rays.
- pull (one's) rank on — to take advantage of one's military rank in enforcing commands or one's high position or seniority in making demands on (a subordinate)
- pure lambda-calculus — Lambda-calculus with no constants, only functions expressed as lambda abstractions.
- pyrenees-atlantiques — a department in SW France. 2978 sq. mi. (7710 sq. km). Capital: Pau.
- pyroligneous alcohol — methyl alcohol.
- quadrantal corrector — either of two soft-iron spheres attached to each side of a binnacle, intended to correct the compass deviation (quadrantal deviation) resulting from magnetism from ferrous metal in a ship.
- quantum field theory — any theory in which fields are treated by the methods of quantum mechanics; each field can then be regarded as consisting of particles of a particular kind, which may be created and annihilated.
- quasi-stellar object — quasar. Abbreviation: QSO.
- queensland arrowroot — a South American and West Indian herb, Canna edulis, having large sheathing leaves, red flowers, and edible rhizomes.
- rachel louise carson — Christopher ("Kit") 1809–68, U.S. frontiersman and scout.
- receivables turnover — A receivables turnover is a measure of cash flow that is calculated by dividing net credit sales by average accounts receivable.
- reciprocal insurance — insurance in which members of a reciprocal exchange, acting through an attorney-in-fact, insure themselves and each other.
- reconcile an account — If you reconcile an account, you compare the items in a bank statement, credit card statement, or vendor statement with the entries on your books and make sure that the statement and books match.
- refuse disposal unit — a unit or part of a sink that disposes of waste food, etc, by grinding
- relative conjunction — a conjunction that introduces a relative clause
- republic of maldives — a republic occupying an archipelago of 1087 coral islands in the Indian Ocean, southwest of Sri Lanka: came under British protection in 1887; became independent in 1965 and a republic in 1968; member of the Commonwealth (1982–2016). The economy and infrastructure were severely damaged in the Indian Ocean tsunami of December 2004. Official language: Divehi. Official religion: (Sunni) Muslim. Currency: rufiyaa. Capital: Malé. Pop: 393 988 (2013 est). Area: 298 sq km (115 sq miles)
- request for proposal — (programming) (RFP) The publication by a prospective software purchaser of details of the required system in order to attract offers by software developers to supply it. Software development under contract starts with the selection of the software developer by the customer. A request for proposal (also called in Britain an "invitation to tender") is the beginning of the selection process.
- rough-legged buzzard — a buzzard, Buteo lagopus, of Europe, Asia, and North America, having feathers covering its legs
- rough-winged swallow — either of two New World swallows of the genus Stelgidopteryx, having outer primary feathers with small barblike hooks on the margins.