18-letter words containing a, d, p, r, e
- per ardua ad astra — through difficulties to the stars: the motto of the RAF
- perceptual defence — the process by which it is thought that certain stimuli are either not perceived or are distorted due to their offensive, unpleasant, or threatening nature
- perforated tracery — tracery, as in early Gothic architecture, formed of cut or pierced slabs of stone set on edge with the flat side outward.
- permanent hardness — hardness of water that cannot be removed by boiling as it results mainly from the presence of calcium and magnesium chlorides and sulphates
- permanent resident — an immigrant who has been given official residential status, often prior to being granted citizenship
- perpetual calendar — a calendar devised to be used for many years, as in determining the day of the week on which a given date falls.
- personal bodyguard — a person employed to protect a particular person
- pescadores-islands — (used with a plural verb) Penghu.
- peter and the wolf — a composition by Sergei Prokofiev written in 1936. It is a children's story with both music and text, spoken by a narrator accompanied by the orchestra
- phosphatidylserine — any of a class of phospholipids occurring in biological membranes and fats
- phthalic anhydride — a white, crystalline, slightly water-soluble solid, C 8 H 4 O 3 , used chiefly in the manufacture of dyes, alkyd resins, and plasticizers.
- pileolated warbler — either of two western subspecies of Wilson's warbler.
- planned parenthood — an organization that gives out information on the planning of the number and spacing of the births of one's children, as through the use of birth-control measures
- play the race card — to introduce the subject of race into a public discussion, esp to gain a strategic advantage
- plenary indulgence — a remission of the total temporal punishment that is still due to sin after absolution. Compare indulgence (def 6).
- point d'angleterre — a bobbin lace in which the design is worked out with either a needle or bobbin.
- point of departure — Nautical. the precise location of a vessel, established in order to set a course, especially in beginning a voyage in open water.
- positively charged — having a positive charge
- postviral syndrome — debilitating condition occurring as a sequel to viral illness
- potassium chloride — a white or colorless, crystalline, water-soluble solid, KCl, used chiefly in the manufacture of fertilizers and mineral water, and as a source of other potassium compounds.
- potassium fluoride — a white, crystalline, hygroscopic, toxic powder, KF, used chiefly as an insecticide, a disinfectant, and in etching glass.
- potential gradient — the rate of change of potential with respect to distance in the direction of greatest change.
- pour cold water on — If someone pours cold water on a plan or idea, they criticize it so much that people lose their enthusiasm for it.
- precedence lossage — /pre's*-dens los'*j/ A misunderstanding of operator precedence resulting in unintended grouping of arithmetic or logical operators when coding an expression. Used especially of mistakes in C code due to the nonintuitively low precedence of "&", "|", "^", "<<" and ">>". For example, the following C expression, intended to test the least significant bit of x, x & 1 == 0 is parsed as x & (1 == 0) which is always zero (false). Some lazy programmers ignore precedence and parenthesise everything. Lisp fans enjoy pointing out that this can't happen in *their* favourite language, which eschews precedence entirely, requiring one to use explicit parentheses everywhere.
- predation pressure — the effect of predation upon a population, resulting in the decrease in size of that population.
- predicate calculus — predicate logic
- prepare the ground — make conditions ready
- presenile dementia — a form of dementia, of unknown cause, starting before a person is old
- 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.
- presidential suite — a suite of rooms, as in a hotel, suitable for a president or other head of state.
- prestidigitization — /pres`t*-di"j*-ti:-zay"sh*n/ 1. A term coined by Daniel Klein <[email protected]> for the act of putting something into digital notation via sleight of hand. 2. Data entry through legerdemain.
- price on sb's head — If there is a price on someone 's head, an amount of money has been offered for the capture or killing of that person.
- primate of england — a title of the archbishop of Canterbury.
- prince of darkness — Satan.
- principal meridian — a meridian line accurately laid out to serve as the reference meridian in land survey
- prisoner's dilemma — (in game theory) a scenario in which the outcome of one person's decision is determined by the simultaneous decisions of the other participants, resulting in a bad outcome for all of them if all act in their own self-interest.
- product acceptance — the verification or acceptance that a manufactured item meets required specifications or standards and is usable for its purpose
- production manager — a supervisor of the budget, crew and other details in the production of a film or play
- programme of study — the prescribed syllabus that pupils must be taught at each key stage in the National Curriculum
- propaganda machine — the group of people, publications, etc, such as of a government, country etc, responsible for the organized dissemination of information, allegations, etc, to assist or damage the cause of a government, movement, etc
- pseudo-anarchistic — a person who advocates or believes in anarchy or anarchism.
- put heads together — the upper part of the body in humans, joined to the trunk by the neck, containing the brain, eyes, ears, nose, and mouth.
- pyramus and thisbe — (in Greek legend) two lovers of Babylon: Pyramus, wrongly supposing Thisbe to be dead, killed himself and she, encountering him in his death throes, did the same
- pyromucic aldehyde — furfural.
- qattara depression — a desert basin in the Libyan Desert, in NW Egypt: lowest point is 435 feet (133 meters) below sea level. 6950 sq. mi. (18,000 sq. km).
- quartz-iodine lamp — a type of tungsten-halogen lamp containing small amounts of iodine and having a quartz envelope, operating at high temperature and producing an intense light for use in car headlamps, etc
- radiation exposure — exposure to radiant energy or to the particles emitted in the transfer of radiant energy, esp the particles and gamma rays emitted in nuclear decay; exposure to radioactive substances
- radiation pressure — the pressure exerted on a surface by electromagnetic radiation or by sound waves.
- radical empiricism — (in the philosophy of William James) the doctrine that the only proper subject matter of philosophy is that which can be defined in terms of experience, and that relations are a part of experience.
- radical expression — an expression in which radical signs appear.