18-letter words containing p, r, e, v, a
- parallel evolution — the independent development of closely corresponding adaptive features in two or more groups of organisms that occupy different but equivalent habitats, as marsupial mammals in Australia and placental mammals on other continents.
- partial derivative — the derivative of a function with respect to one of its variables with all other variables held constant.
- partial evaluation — (compiler, algorithm) (Or "specialisation") An optimisation technique where the compiler evaluates some subexpressions at compile-time. For example, Partial evaluation might change the termination properties of the program if, for example, the expression (x * 0) was reduced to 0 it would terminate even if x (and thus x * 0) did not. It may be necessary to reorder an expression to partially evaluate it, e.g. f x y = (x + y) + 1 g z = f 3 z If we rewrite f: f x y = (x + 1) + y then the expression x+1 becomes a constant for the function g and we can say g z = f 3 z = (3 + 1) + z = 4 + z Partial evaluation of built-in functions applied to constant arguments is known as constant folding. See also full laziness.
- partial-vegetarian — a person who eats mostly plant foods, dairy products, and eggs, and occasionally chicken, fish, and red meat.
- particular average — a loss at sea, as through accident or negligence, that is borne solely by the owner of the lost property. Abbreviation: P.A.
- passive resistance — opposition to a government or to specific governmental laws by the use of noncooperation and other nonviolent methods, as economic boycotts and protest marches.
- passive vocabulary — all the words, collectively, that a person can understand
- passive-aggressive — denoting or pertaining to a personality type or behavior marked by the expression of negative emotions in passive, indirect ways, as through manipulation or noncooperation: a passive-aggressive employee who often misses deadlines.
- pave the way (for) — to prepare the way (for); facilitate the introduction (of)
- pemphigus vulgaris — a potentially fatal blistering skin disease, characterized by large blisters on the skin, mucous membranes of the mouth, genitals, intestines, etc, which eventually rupture and form painful denuded areas from which critical amounts of bodily protein, fluid, and blood may be lost
- physical inventory — To carry out a physical inventory is to count all the stock on hand.
- pneumatic conveyor — a tube through which powdered or granular material, such as cement, grain, etc is transported by a flow of air
- positively charged — having a positive charge
- post-revolutionary — of, pertaining to, characterized by, or of the nature of a revolution, or a sudden, complete, or marked change: a revolutionary junta.
- postviral syndrome — debilitating condition occurring as a sequel to viral illness
- prepositional verb — a combination of verb and preposition, often with idiomatic meaning, differing from other phrasal verbs in that an object must always follow the preposition, as take after in The children take after their mother.
- preservation order — In Britain, a preservation order is an official order that makes it illegal for anyone to alter or destroy something such as an old building or an area of countryside.
- private enterprise — free enterprise (def 1).
- provascular tissue — procambium.
- provision merchant — a person or company in the business of retailing food and other provisions
- psychogalvanometer — a type of galvanometer for detecting and measuring psychogalvanic currents.
- quarter-wave plate — a crystal thin enough to cause a phase difference of 90° between the ordinary and extraordinary rays of polarized light, thereby converting circularly polarized light into plane polarized light.
- rapid eye movement — rapidly shifting, continuous movements of the eyes beneath closed lids during the stage of sleep characterized by dreaming.
- reactive component — the component in an alternating-current circuit that does not contribute power because it is 90° out of phase with the voltage or current.
- recovery operation — the process of locating and retrieving bodies, esp following an explosion or natural disaster
- redevelopment area — an urban area in which all or most of the buildings are demolished and rebuilt
- representativeness — a person or thing that represents another or others.
- sea-level pressure — the atmospheric pressure, at any elevation, reduced by formula to a value approximating the pressure at sea level.
- service department — a repair shop
- special relativity — the state or fact of being relative.
- super royal octavo — a book size, 63⁄4 by 101⁄4 inches
- superior vena cava — See under vena cava.
- supportive therapy — any treatment, such as the intravenous administration of certain fluids, designed to reinforce or sustain the physiological well-being of a patient
- surveyor's compass — an instrument used by surveyors for measuring azimuths.
- the operative word — If you describe a word as the operative word, you want to draw attention to it because you think it is important or exactly true in a particular situation.
- to play favourites — to display favouritism
- to scrape a living — If you say that someone scrapes a living or scratches a living, you mean that they manage to earn enough to live on, but it is very difficult. In American English, you say they scrape out a living or scratch out a living.
- transverse process — a process that projects from the sides of a vertebra.
- universal coupling — a coupling between rotating shafts set at an angle to one another, allowing for rotation in three planes.
- vectorcardiography — a method of determining the direction and magnitude of the electrical forces of the heart.
- venture capitalist — funds invested or available for investment in a new or unproven business enterprise.
- vermiform appendix — a narrow, blind tube protruding from the cecum, having no known useful function, in humans being 3 to 4 inches (8 to 10 cm) long and situated in the lower right-hand part of the abdomen.
- videotape recorder — a device for recording television programs on magnetic tape for delayed transmission or for storage.
- vulcan nerve pinch — (jargon) (Or "three-finger salute", Vulcan death grip; from the old "Star Trek" TV series via Commodore Amiga hackers) The keyboard combination that forces a soft boot or jump to ROM monitor (on machines that support such a feature). On an Amiga this is done with Ctrl/Right Amiga/Left Amiga; on IBM PCs and many microcomputers it is Ctrl/Alt/Del; on Suns, L1-A; on some Macintoshes, it is
- ! Silicon Graphics users are obviously the most dextrous however, as these machines use the five-finger combination: Left Shift/Left Ctrl/Left Alt/Keypad Divide/F12. Compare quadruple bucky.