21-letter words containing p, r, e, t, a, c
- main-topsail schooner — a two-masted or three-masted schooner having square topsails on the foremast and mainmast: a jackass brig or jackass bark.
- manufacturing process — chain of production
- mass-market paperback — a relatively inexpensive paperbound book, typically measuring about 4½ × 7 inches (11 × 18 cm), that is distributed on newsstands, in supermarkets, etc., as well as in bookstores.
- megaspore mother cell — a diploid cell in plants that undergoes meiosis to create four haploid megaspores.
- metabotropic receptor — an indirect receptor which initiates an intracellular biochemical cascade after it is triggered by an agonistic ligand
- metropolitan district — any of the districts making up the metropolitan counties of England: since 1986 they have functioned as unitary authorities, forming the sole principal tier of local government. Each metropolitan district has an elected council responsible for education, social services, etc
- microware corporation — Authors of OS-9. Address: Des Moines, Iowa, USA.
- modern apprenticeship — an arrangement that allows a school leaver to gain vocational qualifications while being trained in a job
- mother-of-pearl cloud — nacreous cloud.
- motion-picture camera — a sequence of consecutive pictures of objects photographed in motion by a specially designed camera (motion-picture camera) and thrown on a screen by a projector (motion-picture projector) in such rapid succession as to give the illusion of natural movement.
- multilayer perceptron — A network composed of more than one layer of neurons, with some or all of the outputs of each layer connected to one or more of the inputs of another layer. The first layer is called the input layer, the last one is the output layer, and in between there may be one or more hidden layers.
- national park service — a division of the Department of the Interior, created in 1916, that administers national parks, monuments, historic sites, and recreational areas.
- near-death experience — A near-death experience is a strange experience that some people who have nearly died say they had when they were unconscious.
- negative prescription — the barring of adverse claims to property, etc, after a specified period of time has elapsed, allowing the possessor to acquire title
- netware core protocol — (networking) (NCP) A Novell trademark for the protocol used to access Novell NetWare file and print service functions. It uses an underlying IPX or IP transport protocol.
- non-repeating decimal — a decimal representation of any irrational number, having the property that no sequence of digits is repeated ad infinitum.
- nonproportional cover — Nonproportional cover is reinsurance cover such as excess of loss reinsurance where the reinsurer's liability is not calculated as a proportion of the insurance.
- north pacific current — a warm current flowing eastward across the Pacific Ocean.
- nuclear power station — a station or plant where nuclear energy is converted into heat, electricity, etc
- old spanish practices — irregular practices among a group of workers to gain increased financial allowances, reduced working hours, etc
- open telecom platform — (communications, library) (OTP) A set of standard, open source libraries and tools for use with Erlang.
- open trading protocol — Internet Open Trading Protocol
- operational semantics — (theory) A set of rules specifying how the state of an actual or hypothetical computer changes while executing a program. The overall state is typically divided into a number of components, e.g. stack, heap, registers etc. Each rule specifies certain preconditions on the contents of some components and their new contents after the application of the rule. It is similar in spirit to the notion of a Turing machine, in which actions are precisely described in a mathematical way. Compuare axiomatic semantics, denotational semantics.
- optical double (star) — double star (sense 2)
- orthogonal projection — a two-dimensional graphic representation of an object in which the projecting lines are at right angles to the plane of the projection. Also called orthogonal projection. Compare isometric (def 5).
- pacific standard time — See under standard time.
- painter and decorator — a person who paints and decorates houses as a trade
- paper over the cracks — conceal flaws or problems
- paper-white narcissus — a white-flowered variety of Narcissus tazetta, often forced for indoor bloom.
- paradoxical intention — (in psychotherapy) the deliberate practice of a neurotic habit or thought, undertaken in order to remove it
- parametric statistics — the branch of statistics concerned with data measurable on interval or ratio scales, so that arithmetic operations are applicable to them, enabling parameters such as the mean of the distribution to be defined
- partial reinforcement — the process of randomly rewarding an organism for making a response on only some of the occasions it makes it
- partition coefficient — the ratio of the concentrations of a substance in two heterogenous phases in equilibrium with each other
- path coverage testing — (testing) Testing a program by examining which lines of executable code are visited (as in code coverage testing) and also the ways of getting to each line of code and the subsequent sequence of execution. Path coverage testing is the most comprehensive type of testing that a test suite can provide. It can find more bugs, especially those that are caused by data coupling. However, path coverage is hard and usually only used for small and/or critical sections of code.
- pathfinder prospectus — a prospectus regarding the flotation of a new company that contains only sufficient details to test the market reaction
- performance indicator — a quantitative or qualitative measurement, or any other criterion, by which the performance, efficiency, achievement, etc of a person or organization can be assessed, often by comparison with an agreed standard or target
- person-to-person call — a call to a specified person; if that person cannot take the call there is no charge
- phrase structure tree — Linguistics. a structural representation of a sentence in the form of an inverted tree, with each node of the tree labeled according to the phrasal constituent it represents.
- phrase-structure rule — a rule that generates a sentence or other syntactic construction from words and phrases and identifies its constituent structure.
- picture quality scale — (graphics) (PQS) A system for rating image quality based upon features of images that affect their perception by the human eye, rather than the traditional signal-to-noise ratio which examines differences for every single pixel.
- piezoelectric ceramic — any ceramic that exhibits piezoelectric properties.
- piezoelectric crystal — a crystal, such as quartz, that produces a potential difference across its opposite faces when under mechanical stress
- pipelined burst cache — Pipeline Burst Cache
- place of articulation — the location at which two speech organs approach or come together in producing a speech sound, as in the contact of the tongue and the teeth to form a dental sound. Also called point of articulation. Compare articulator (def 2).
- place of safety order — (in Britain) under the Children and Young Persons Act 1969, an order granted by a justice to a person or agency granting authority to detain a child or young person and take him or her to a place of safety for not more than 28 days, because of the child's actual or likely ill-treatment or neglect, etc
- plate glass insurance — Plate glass insurance is insurance coverage against damage to or breakage of large panes of glass such as shop windows.
- political correctness — Political correctness is the attitude or policy of being extremely careful not to offend or upset any group of people in society who have a disadvantage, or who have been treated differently because of their sex, race, or disability.
- politically incorrect — not politically correct; potentially offensive to a particular group of people: politically incorrect jokes.
- polygenic inheritance — the heredity of complex characters that are determined by a large number of genes, each one usually having a relatively small effect.
- pomp and circumstance — ceremony