18-letter words containing a, p, r, i
- at your fingertips — If you say that something is at your fingertips, you approve of the fact that you can reach it easily or that it is easily available to you.
- athletic supporter — jockstrap
- 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
- auditory phonetics — the branch of phonetics concerned with the perception of speech sounds by humans
- australopithecines — Plural form of australopithecine.
- authorized capital — the total amount of value of the shares that a company is allowed to distribute
- autobiographically — In a autobiographical manner.
- automatic exposure — the automatic adjustment of the lens aperture and shutter speed of a camera by a control mechanism
- avoirdupois weight — a British and American system of weights based on a pound of 16 ounces
- baritone saxophone — the second lowest instrument in the family of saxophones
- behaviour patterns — the characteristic ways in which a person or animal acts
- benchmark position — a public service job used for comparison with a similar position, such as a position in commerce, for wage settlements
- 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.
- biological parents — the biological mother and father of a child
- biological therapy — biotherapy
- bipolar transistor — (electronics) A transistor made from a sandwich of n- and p-type semiconductor material: either npn or pnp. The middle section is known as the "base" and the other two as the "collector" and "emitter". When used as an amplifying element, the base to emitter junction is in a "forward-biased" (conducting) condition, and the base to collector junction is "reverse-biased" or non-conducting. Small changes in the base to emitter current (the input signal) cause either holes (for pnp devices) or free electrons (for npn) to enter the base from the emitter. The attracting voltage of the collector causes the majority of these charges to cross into and be collected by the collector, resulting in amplification. Contrast field effect transistor.
- blocking capacitor — a capacitor that blocks the passage of direct current but allows alternating current to pass
- brazilian sapphire — a blue variety of tourmaline used as a gem: not a true sapphire.
- 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
- c-reactive protein — a globulin in the blood produced by the liver in response to inflammation
- calcium propionate — a white, water-soluble powder, CaC 6 H 10 O 4 , used in bakery products to inhibit the growth of fungi.
- calliper compasses — an instrument for measuring internal or external dimensions, consisting of two steel legs hinged together
- camp david accords — a peace treaty between Israel and Egypt issuing from talks at Camp David between Egyptian President Sadat, Israeli Prime Minister Begin, and the host, U.S. President Carter: signed in 1979.
- campaign furniture — furniture, as chests or desks, having metal hinges on the corners and handles on the sides.
- cape breton island — an island off SE Canada, in NE Nova Scotia, separated from the mainland by the Strait of Canso: its easternmost point is Cape Breton. Pop: 132 298 (2006). Area: 10 280 sq km (3970 sq miles)
- carthaginian peace — the treaty by which Rome reduced Carthage to the status of a puppet state in 201 b.c.
- cassiopeia's chair — the five brightest stars in the constellation Cassiopeia that seem to form the shape of a W or M
- castration complex — an unconscious fear of having one's genitals removed, as a punishment for wishing to have sex with a parent
- caterpillar hunter — any of various carabid beetles of the genus Calosoma, of Europe and North America, which prey on the larvae of moths and butterflies
- central projection — a projection of one plane onto a second plane such that a point on the first plane and its image on the second plane lie on a straight line through a fixed point not on either plane.
- cepheid (variable) — any of a class of pulsating, yellow, supergiant stars whose brightness varies in regular periods: from the period-luminosity relation, the distance of such a star can be determined
- chagos archipelago — group of islands in the Indian Ocean 1,180 mi (1,899 km) northeast of Mauritius, comprising the British Indian Ocean Territory: chief island, Diego Garcia
- character graphics — ASCII art
- checkpoint charlie — a crossing between East and West Berlin during the Cold War
- chemical pregnancy — a pregnancy that is confirmed by a pregnancy test but not by clinical signs and terminates before clinical signs can be observed.
- christine de pisan — ?1364–?1430, French poet and prose writer, born in Venice. Her works include ballads, rondeaux, lays, and a biography of Charles V of France
- christmas shopping — shopping especially for Christmas presents, but also for Christmas food and drink, and all the other things required over the Christmas period.
- chromatic printing — printing from blocks or types inked with various colours
- chromolithographer — One engaged in chromolithography.
- chromolithographic — Pertaining to, or made by, chromolithography.
- chronostratigraphy — The branch of geology concerned with establishing the absolute ages of strata.
- citizenship papers — the document stating that a naturalized person has been formally declared a citizen
- claustrophobically — In a claustrophobic way.
- closed corporation — a corporation the stock of which is owned by a small number of persons and is rarely traded on the open market
- closed scholarship — a scholarship for which only certain people, such as those from a particular school or with a particular surname, are eligible
- combined operation — a military operation carried out jointly by allied forces
- commando operation — a major operation for treatment of cancer of the head and neck, involving removal of many facial structures and subsequent surgical reconstruction
- comparative method — a body of procedures and criteria used by linguists to determine whether and how two or more languages are related and to reconstruct forms of their hypothetical parent language.
- comparison shopper — an employee of a retail store hired to visit competing stores in order to gather information regarding styles, quality, prices, etc., of merchandise offered by competitors.