18-letter words containing a, e, r, i, u
- population figures — population totals; statistics relating to the size of populations
- porcupine anteater — an echidna or spiny anteater.
- portable equipment — Portable equipment is electrical equipment that can easily be moved from one place to another while in operation or while connected to the supply.
- portuguese guinean — of or relating to Portuguese Guinea, a former name for Guinea-Bissau, or its inhabitants
- post-revolutionary — of, pertaining to, characterized by, or of the nature of a revolution, or a sudden, complete, or marked change: a revolutionary junta.
- potassium chlorate — a white or colorless, crystalline, water-soluble, poisonous solid, KClO 3 , used chiefly as an oxidizing agent in the manufacture of explosives, fireworks, matches, bleaches, and disinfectants.
- 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.
- potassium myronate — sinigrin.
- preantepenultimate — third from the end.
- predation pressure — the effect of predation upon a population, resulting in the decrease in size of that population.
- predicate calculus — predicate logic
- presidential suite — a suite of rooms, as in a hotel, suitable for a president or other head of state.
- pressure altimeter — an aneroid barometer adapted for measuring altitude by converting the indicated atmospheric pressure to altitude according to a standard relationship.
- presumption of law — a presumption based upon a policy of law or a general rule and not upon the facts or evidence in an individual case.
- primus inter pares — (of males) first among equals.
- principal argument — the radian measure of the argument between −π and π of a complex number. Compare argument (def 8c).
- prison authorities — the people in charge of running a prison
- procrustean string — (programming) A fixed-length string. If a string value is too long for the allocated space, it is truncated to fit; and if it is shorter, the empty space is padded, usually with space characters. This is an allusion to Procrustes, a legendary robber of ancient Attica. He bound his victims to a bed, and if they were shorter than the bed, he stretched their limbs until they would fit; if their limbs were longer, he lopped them off.
- production manager — a supervisor of the budget, crew and other details in the production of a film or play
- property insurance — insurance coverage for land and housing
- provascular tissue — procambium.
- pseudo-anarchistic — a person who advocates or believes in anarchy or anarchism.
- psychotherapeutics — psychotherapy.
- pulmonary embolism — the blockage of a pulmonary artery, often by a blood clot, that stops the flow of blood to the lungs and which can result in death if untreated
- pulmonic airstream — a current of lung air set in motion by the respiratory muscles in the production of speech.
- purchasing officer — the member of staff in an organization who is responsible for buying goods or products
- 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.
- quadratic equation — an equation containing a single variable of degree 2. Its general form is ax 2 + bx + c = 0, where x is the variable and a, b, and c are constants (a ≠ 0).
- quality controller — a person responsible for checking that the goods or services produced by an organization are of an acceptable standard
- quality of service — (communications, networking) (QoS) The performance properties of a network service, possibly including throughput, transit delay, priority. Some protocols allow packets or streams to include QoS requirements.
- quantity surveying — the action or profession of a person who estimates the cost of the materials and labour necessary for a construction job
- quarry-tiled floor — a floor covered with square or diamond-shaped unglazed floor tiles
- quarterlife crisis — a crisis that may be experienced in one's twenties, involving anxiety over the direction and quality of one's life
- 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
- quick off the mark — If you are quick off the mark, you are quick to understand or respond to something. If you are slow off the mark, you are slow to understand or respond to something.
- quinacrine mustard — a nitrogen mustard derived from mepacrine and used as a stain for chromosomes
- quite the contrary — not at all, the very opposite
- 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.
- real-time computer — a computer that can process data or information almost immediately
- rear its ugly head — the upper part of the body in humans, joined to the trunk by the neck, containing the brain, eyes, ears, nose, and mouth.
- reciprocating pump — A reciprocating pump is a pump which uses a backward and forward movement to move a fluid.
- recruitment agency — company that places job candidates
- reduction strategy — (theory) An algorithm for deciding which redex(es) to reduce next. Different strategies have different termination properties in the presence of recursive functions or values. See string reduction, normal order reduction, applicative order reduction, parallel reduction
- regular expression — 1. (text, operating system) (regexp, RE) One of the wild card patterns used by Perl and other languages, following Unix utilities such as grep, sed, and awk and editors such as vi and Emacs. Regular expressions use conventions similar to but more elaborate than those described under glob. A regular expression is a sequence of characters with the following meanings (in Perl, other flavours vary): An ordinary character (not one of the special characters discussed below) matches that character. A backslash (\) followed by any special character matches the special character itself. The special characters are: "." matches any character except newline; "RE*" (where RE is any regular expression and the "*" is called the "Kleene star") matches zero or more occurrences of RE. If there is any choice, the longest leftmost matching string is chosen. "^" at the beginning of an RE matches the start of a line and "$" at the end of an RE matches the end of a line. (RE) matches whatever RE matches and \N, where N is a digit, matches whatever was matched by the RE between the Nth "(" and its corresponding ")" earlier in the same RE. Many flavours use \(RE\) instead of just (RE). The concatenation of REs is a RE that matches the concatenation of the strings matched by each RE. RE1 | RE2 matches whatever RE1 or RE2 matches. \< matches the beginning of a word and \> matches the end of a word. Many flavours use "\b" instead as the special character for "word boundary". RE{M} matches M occurences of RE. RE{M,} matches M or more occurences of RE. RE{M,N} matches between M and N occurences. Other flavours use RE\{M\} etc. Perl provides several "quote-like" operators for writing REs, including the common // form and less common ??. A comprehensive survey of regexp flavours is found in Friedl 1997 (see below). 2. Any description of a pattern composed from combinations of symbols and the three operators: Concatenation - pattern A concatenated with B matches a match for A followed by a match for B. Or - pattern A-or-B matches either a match for A or a match for B. Closure - zero or more matches for a pattern. The earliest form of regular expressions (and the term itself) were invented by mathematician Stephen Cole Kleene in the mid-1950s, as a notation to easily manipulate "regular sets", formal descriptions of the behaviour of finite state machines, in regular algebra.
- regular tertiaries — of the third order, rank, stage, formation, etc.; third.
- reinsurance treaty — A reinsurance treaty is a contract that defines the terms of reinsurance business.
- relative frequency — the ratio of the number of times an event occurs to the number of occasions on which it might occur in the same period.