19-letter words containing a, c, l, o, s
- national assistance — (in Britain) formerly a weekly allowance paid to certain people by the state to bring their incomes up to minimum levels established by law
- national characters — (character) Characters with accents and other diacritical marks that are used in certain written languages (that are based on the Roman alphabet) but not in others, particularly not in English. A standard list is ISO Latin 1.
- national serviceman — a soldier undertaking compulsory military service
- natural catastrophe — A natural catastrophe is an unexpected event, caused by nature, such as an earthquake or flood, in which there is a lot of suffering, damage, or death.
- newcastle upon tyne — 1st Duke of, Pelham-Holles, Thomas.
- newtonian telescope — a reflecting telescope in which a mirror or reflecting prism is mounted on the axis near the eyepiece so that the image may be viewed from outside the telescope tube at right angles to the axis.
- nicolaus copernicus — Nicolaus [nik-uh-ley-uh s] /ˌnɪk əˈleɪ əs/ (Show IPA), (Mikolaj Kopernik) 1473–1543, Polish astronomer who promulgated the now accepted theory that the earth and the other planets move around the sun (the Copernican System)
- north-central state — a state of N Nigeria. Capital: Kaduna. Pop: 4 438 007 (1995 est). Area: 46 053 sq km (17 781 sq miles)
- obsolescence clause — a clause in an insurance policy that takes account of the obsolescence of the item insured in order to lower the amount to be paid out in the event of a claim
- 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).
- oil-catalyst slurry — Oil-catalyst slurry is a heavy aromatic by-product of a refinery's fluid catalytic cracking unit, that forms a small part of global fuel oil supply.
- 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.
- old spanish customs — irregular practices among a group of workers to gain increased financial allowances, reduced working hours, etc
- olive-backed thrush — Swainson's thrush.
- optical double star — two stars that appear as one if not viewed through a telescope with adequate magnification, such as two stars that are separated by a great distance but are nearly in line with each other and an observer (optical double star) or those that are relatively close together and comprise a single physical system (physical double star)
- oscillating circuit — a circuit producing electrical oscillations.
- parallel processing — extending in the same direction, equidistant at all points, and never converging or diverging: parallel rows of trees.
- particle dispersoid — A particle dispersoid is a suspension of solid particles in a gas.
- particle separation — a rule that moves the particle of a phrasal verb, thus deriving a sentence like He looked the answer up from a structure that also underlies He looked up the answer
- particular solution — a solution of a differential equation containing no arbitrary constants.
- pastoral counseling — the use of psychotherapeutic techniques by trained members of the clergy to assist parishioners who seek help for personal or emotional problems.
- peroxysulfuric acid — persulfuric acid (def 1).
- personal watercraft — a jet-propelled boat ridden like a motorcycle.
- phacoemulsification — the removal of a cataract by first liquefying the affected lens with ultrasonic vibrations and then extracting it by suction.
- phakoemulsification — the removal of a cataract by first liquefying the affected lens with ultrasonic vibrations and then extracting it by suction.
- philosophical logic — the branch of philosophy that studies the relationship between formal logic and ordinary language, esp the extent to which the former can be held accurately to represent the latter
- pillars of hercules — the two promontories at the E end of the Strait of Gibraltar: the Rock of Gibraltar on the European side and the Jebel Musa on the African side; according to legend, formed by Hercules
- plastic deformation — In plastic deformation a material changes shape when a stress is applied to it and does not go back to its original state when the stress is removed.
- police headquarters — building where police are stationed
- political scientist — A political scientist is someone who studies, writes, or lectures about political science.
- political-scientist — a social science dealing with political institutions and with the principles and conduct of government.
- polyphosphoric acid — any one of a series of oxyacids of phosphorus with the general formula Hn+2PnO3n+1. The first member is pyrophosphoric acid (n = 2) and the series includes the highly polymeric metaphosphoric acid. The higher acids exist in an equilibrium mixture
- population genetics — the branch of genetics concerned with the hereditary makeup of populations.
- port jackson willow — an Australian acacia tree, Acacia cyanophylla, introduced in the 19th century into South Africa, where it is now regarded as a pest
- post-and-rail fence — a fence constructed of upright wooden posts with horizontal timber slotted through it
- posttranscriptional — Genetics, Biochemistry. occurring after the formation of RNA from DNA but before the RNA strand leaves the nucleus.
- prismatic telescope — a telescope having an eyepiece at the side or top equipped with a reflecting prism, used for taking sights at steep angles.
- professional advice — advice given by someone trained in a particular and relevant profession or job
- professional school — a postgraduate school or college which trains students for a particular profession
- property speculator — a person who takes part in property speculation
- propositional logic — (logic) (or "propositional calculus") A system of symbolic logic using symbols to stand for whole propositions and logical connectives. Propositional logic only considers whether a proposition is true or false. In contrast to predicate logic, it does not consider the internal structure of propositions.
- pseudo-biographical — of or relating to a person's life: He's gathering biographical data for his book on Milton.
- pseudo-intellectual — a person exhibiting intellectual pretensions that have no basis in sound scholarship.
- pseudopsychological — of or relating to psychology.
- psychological novel — a novel that focuses on the complex mental and emotional lives of its characters and explores the various levels of mental activity.
- psychophysiological — of or relating to psychophysiology.
- psychotechnological — of or relating to psychotechnology
- puerperal psychosis — a mental disorder sometimes occurring in women after childbirth, characterized by deep depression, delusions of the child's death, and homicidal feelings towards the child
- quantum electronics — the application of quantum mechanics and quantum optics to the study and design of electronic devices
- raise one's hackles — one of the long, slender feathers on the neck or saddle of certain birds, as the domestic rooster, much used in making artificial flies for anglers.