19-letter words containing a, l, r, o, u, n
- occupational hazard — a danger or hazard to workers that is inherent in a particular occupation: Silicosis is an occupational hazard of miners.
- oceanus procellarum — (Ocean of Storms) the largest dark plain on the face of the moon, in the second and third quadrants: about 2 million square miles (5.2 million sq. km).
- old church slavonic — the oldest attested Slavic language, an ecclesiastical language written first by Cyril and Methodius in a Bible translation of the 9th century and continued in use for about two centuries. It represents the South Slavic, Bulgarian dialect of 9th-century Salonika with considerable addition of other South and West Slavic elements. Abbreviation: OCS.
- oriental fruit moth — a moth, Grapholitha molesta, introduced into the U.S. from Asia, the larvae of which infest and feed on the twigs and fruits of peach, plum, and related trees.
- oscillating circuit — a circuit producing electrical oscillations.
- oxyacetylene burner — a blowpipe for cutting or welding metals at high temperatures
- particular solution — a solution of a differential equation containing no arbitrary constants.
- party-column ballot — Indiana ballot.
- pastoral counseling — the use of psychotherapeutic techniques by trained members of the clergy to assist parishioners who seek help for personal or emotional problems.
- perpetual adoration — uninterrupted adoration of the Blessed Sacrament.
- perpetual inventory — a form of stock control in which running records are kept of all acquisitions and disposals
- pneumoencephalogram — an encephalogram made after the replacement of the cerebrospinal fluid by air or gas, rarely used since the development of the CAT scanner.
- pointe-aux-trembles — a city in S Quebec, in E Canada, N of Montreal, on the St. Lawrence.
- popular sovereignty — the doctrine that sovereign power is vested in the people and that those chosen to govern, as trustees of such power, must exercise it in conformity with the general will.
- population pressure — the force exerted by a growing population upon its environment, resulting in dispersal or reduction of the population.
- preproduction trial — a trial to test a prototype of a product before the product goes into full-scale production
- procedural language — (language) Any programming language in which the programmer specifies an explicit sequences of steps to follow to produce a result (an algorithm). The term should not be confused with "imperative language" - a language that specifies explicit manipulation of state. An example (non-imperative) procedural language is LOGO, which specifies sequences of steps to perform but does not have an internal state. Other procedural languages include Basic, Pascal, C, and Modula-2. Both procedural and imperative languages are in contrast to declarative languages, in which the programmer specifies neither explicit steps nor explicit state manipulation.
- production platform — offshore power station
- provably unsolvable — The set or property of problems for which no algorithm at all exists. E.g. the Halting Problem. See also provably difficult.
- pseudo-experimental — pertaining to, derived from, or founded on experiment: an experimental science.
- pseudo-professional — following an occupation as a means of livelihood or for gain: a professional builder.
- quantum electronics — the application of quantum mechanics and quantum optics to the study and design of electronic devices
- queen's regulations — (in Britain and certain other Commonwealth countries when the sovereign is female) the code of conduct for members of the armed forces
- rap on the knuckles — a mild reprimand or light sentence
- reconceptualization — to form into a concept; make a concept of.
- recurrence relation — (mathematics) An equation that defines each element of a sequence in terms of one or more earlier elements. E.g. The Fibonacci sequence, X[1] = 1 X[2] = 1 X[n] = X[n-1] + X[n-2] Some recurrence relations can be converted to "closed form" where X[n] is defined purely in terms of n, without reference to earlier elements.
- reduction potential — (in a galvanic cell) the potential of the electrode at which reduction occurs.
- regular icosahedron — an icosahedron in which each of the faces is an equilateral triangle
- reindustrialization — the revitalization of an industry or industrial society through government aid and tax incentives, modernization of factories and machinery, etc.
- relational calculus — (database) An operational methodolgy, founded on predicate calculus, dealing with descripitive expressions that are equivalent to the operations of relational algebra. Codd's reduction algorithm can convert from relational calculus to relational algebra. Two forms of the relational calculus exist: the tuple calculus and the domain calculus.
- relational language — (language) Any kind of programming language that specifies output in terms of some property and some arguments. For example, if Tom has two brothers, Dick and Harry, a relational language will respond to the query "Who is Tom's brother?" with either Dick or Harry. Notice that unlike functional languages, relational languages do not require a unique output for each predicate/argument pair. Prolog is the best known relational language.
- religious education — religion as school subject
- republic of ireland — John, 1838–1918, U.S. Roman Catholic clergyman and social reformer, born in Ireland: archbishop of St. Paul, Minn., 1888–1918.
- republic of vietnam — the name (from 1955–75) for South Vietnam, as an independent republic, following the division of the country in 1954 into North Vietnam and South Vietnam
- reticular formation — a network of neurons in the brainstem involved in consciousness, regulation of breathing, the transmission of sensory stimuli to higher brain centers, and the constantly shifting muscular activity that supports the body against gravity.
- reticuloendothelial — pertaining to, resembling, or involving cells of the reticuloendothelial system.
- rhetorical question — a question asked solely to produce an effect or to make an assertion and not to elicit a reply, as “What is so rare as a day in June?”.
- right circular cone — a cone whose surface is generated by lines joining a fixed point to the points of a circle, the fixed point lying on a perpendicular through the center of the circle.
- scale down (or up) — to reduce (or increase), often according to a fixed ratio or proportion
- screen actors guild — a labor union for motion-picture performers, founded in 1933. Abbreviation: SAG.
- sea of tranquillity — Astronomy. Mare Tranquillitatis.
- secondary qualities — one of the qualities attributed by the mind to an object perceived, such as color, temperature, or taste.
- self-congratulating — the expression or feeling of uncritical satisfaction with oneself or one's own accomplishment, good fortune, etc.; complacency.
- self-congratulation — the expression or feeling of uncritical satisfaction with oneself or one's own accomplishment, good fortune, etc.; complacency.
- self-congratulatory — the expression or feeling of uncritical satisfaction with oneself or one's own accomplishment, good fortune, etc.; complacency.
- semiconductor laser — a laser in which a semiconductor is the light-emitting source, used in many medical procedures.
- senatorial courtesy — the practice in the U.S. Senate of confirming only those presidential appointees approved by both senators from the state of the appointee, or by the senior senator of the president's party.
- sexual inter-course — genital contact, especially the insertion of the penis into the vagina followed by orgasm; coitus; copulation.
- sexual reproduction — reproduction involving the union of gametes.
- sexual stereotyping — the formation or promotion of a fixed general idea or image of how men and women will behave