18-letter words containing a, r, n
- airman first class — the third lowest enlisted rank in the US Air Force, above airman and below senior airman
- airspeed indicator — a dial that indicates the airspeed at which an aircraft is travelling
- alarm clock briton — a British worker with a moderate income, whose daily routine involves preparing children for school and going out to work
- albert bruce sabin — Albert Bruce, 1906–93, U.S. physician, born in Poland: developed Sabin vaccine.
- albrecht waldstein — Albrecht von [German ahl-brekht fuh n] /German ˈɑl brɛxt fən/ (Show IPA), Wallenstein, Albrecht Wenzel Eusebius von.
- alexander hamilton — Alexander, 1757–1804, American statesman and writer on government: the first Secretary of the Treasury 1789–97; mortally wounded by Aaron Burr in a duel.
- alexander i island — an island of Antarctica, west of Palmer Land, in the Bellingshausen Sea. Length: about 378 km (235 miles)
- algebraic equation — an equation in the form of a polynomial having a finite number of terms and equated to zero, as 2 x 3 + 4 x 2 − x + 7 = 0.
- algebraic function — any function which can be constructed in a finite number of steps from the elementary operations and the inverses of any function already constructed
- algebraic notation — the standard method of denoting the squares on the chessboard, by allotting a letter, a, b, c, up to h, to each of the files running up the board from White's side, starting from the left, and a number to each of the ranks across the board, starting with White's first rank
- alkali metaprotein — a metaprotein derived by means of a hydrolytic alkali.
- allegheny barberry — a shrub, Berberis canadensis, of North America, resembling the common barberry of Europe, but having leaves with grayish undersides.
- almoner's cupboard — a cupboard with pierced doors, formerly used as a storage place for food.
- alternate straight — a hand consisting of five cards following one another by two in order of denomination, as a five, seven, nine, jack, and king, being of special value in certain games.
- alternating series — a series, usually infinite, in which successive terms have opposite signs, as 1 − ½ + ¼ − ⅛ +. ….
- alternative comedy — a style of comedy originating in the UK in the 1980s that seeks to avoid racist or sexist stereotypes, and usually puts forward left-wing, anti-establishment views
- alternative energy — a form of energy derived from a natural source, such as the sun, wind, tides, or waves
- alternative school — any public or private school having a special curriculum, especially an elementary or secondary school offering a more flexible program of study than a traditional school.
- alumina trihydrate — a crystalline, water-insoluble powder, Al(OH) 3 or Al 2 O 3 ⋅3H 2 O, obtained chiefly from bauxite: used in the manufacture of glass, ceramics, and printing inks, in dyeing, and in medicine as an antacid and in the treatment of ulcers.
- aluminum hydroxide — a white powder, Al(OH)3, obtained from bauxite and used to make glass, paper, etc. and in antacids
- amdahl corporation — (company) A US computer manufacturer. Amdahl is a major supplier of large mainframes, UNIX and Open Systems software and servers, data storage subsystems, data communications products, applications development software, and a variety of educational and consulting services. Amdahl products are sold in more than 30 countries for use in both open systems and IBM plug-compatible mainframe computing environments. Quarterly sales $397M, profits $13M (Aug 1994). In 1997 Amdahl became a division of Fujitsu.
- american brooklime — any of various speedwells found along brooks, in marshes, etc., as Veronica americana (American brooklime) a creeping plant having leafy stems and loose clusters of small blue flowers.
- american chameleon — anole: lizards of this type (family Iguanidae) are incorrectly called “chameleons”
- american civil war — the war in the U.S. between the North and the South, 1861–65.
- american cockroach — a large, reddish-brown cockroach, Periplaneta americana, found originally in the southern U.S. but now widely distributed.
- american cranberry — See under cranberry (def 1).
- ammonium carbamate — a white soluble crystalline compound produced by reaction between dry ammonia and carbon dioxide and used as a nitrogen fertilizer. Formula: (NH4)CO2NH2
- ammonium carbonate — an unstable pungent soluble white powder that is a double salt of ammonium bicarbonate and ammonium carbamate: used in the manufacture of baking powder, smelling salts, and ammonium compounds. Formula: (NH4)HCO3.(NH4)CO2NH2
- ammonium hydroxide — a compound existing only in aqueous solution, formed when ammonia dissolves in water to form ammonium ions and hydroxide ions. Formula: NH4OH
- ammonium purpurate — murexide.
- an overgrown child — an adult whose behaviour is characteristic of a child
- analogue recording — a sound recording process in which an audio input is converted into an analogous electrical waveform
- analytical reagent — a chemical compound of a known high standard of purity
- andorre la vieille — French name for the capital of Andorra, situated in the west of the principality. Pop: 22 035 (2003 est)
- andrew file system — (operating system, storage) (AFS) The distributed file system of the Andrew Project, adopted by the OSF as part of their Distributed Computing Environment.
- angel of the north — a steel sculpture of an angel with outstretched wings, created in 1998 by British sculptor Antony Gormley, which stands on a hilltop outside Gateshead, NE England. It stands 20 m (85 ft) high and has a wingspan of 54 m (175 ft)
- angiocardiographic — Relating to angiocardiography.
- angular dispersion — a measure of the angular separation of light rays of different wavelength or color traversing a prism or diffraction grating, equal to the rate of change of the angle of deviation with respect to the change in wavelength.
- anniversary dinner — a dinner held to celebrate an event that occurred in some previous year
- anterior pituitary — a small, somewhat cherry-shaped double structure attached by a stalk to the base of the brain and constituting the master endocrine gland affecting all hormonal functions in the body, consisting of an anterior region ((anterior pituitary) or (adenohypophysis)) that develops embryonically from the roof of the mouth and that secretes growth hormone, LH, FSH, ACTH, TSH, and MSH, a posterior region ((posterior pituitary) or (neurohypophysis)) that develops from the back of the forebrain and that secretes the hormones vasopressin and oxytocin, and an intermediate part (pars intermedia) derived from the anterior region but joined to the posterior region, that secretes the hormone MSH in lower vertebrates.
- anthropocentricity — the state or quality of being anthropocentric.
- anthropomorphising — Present participle of anthropomorphise.
- anthropomorphizing — Present participle of anthropomorphize.
- anthropomorphously — In an anthropomorphous manner; in a manner resembling that of a human.
- anti-aircraft fire — the discharging of weapons, artillery, etc aimed at destroying enemy aircraft
- anti-authoritarian — favoring complete obedience or subjection to authority as opposed to individual freedom: authoritarian principles; authoritarian attitudes.
- anti-commercialism — the principles, practices, and spirit of commerce.
- anti-masonic party — a former political party (1826–35) that opposed Freemasonry in civil affairs.
- anti-revolutionary — of, pertaining to, characterized by, or of the nature of a revolution, or a sudden, complete, or marked change: a revolutionary junta.
- anticholinesterase — any of a group of substances that inhibit the action of cholinesterase