21-letter words containing c, a, o
- programmed cell death — a normal, genetically regulated process leading to the death of cells and triggered by the presence or absence of certain stimuli, as DNA damage.
- progressive education — any of various reformist educational philosophies and methodologies since the late 1800s, applied especially to elementary schools, that reject the rote recitation and strict discipline of traditional, single-classroom teaching, favoring instead more stimulation of the individual pupil as well as group discussion, more informality in the classroom, a broader curriculum, and use of laboratories, gymnasiums, kitchens, etc., in the school.
- protective coloration — coloration or anything likened to it that eliminates or reduces visibility or conspicuousness.
- protestant work ethic — work ethic.
- psychological primary — one of a set of perceived colours (red, yellow, blue, green, black, and white) that can be used to characterize all other perceived colours
- psychological warfare — the use of propaganda, threats, and other psychological techniques to mislead, intimidate, demoralize, or otherwise influence the thinking or behavior of an opponent.
- psychomotor agitation — agitation (def 3).
- psychomotor-agitation — the act or process of agitating; state of being agitated: She left in great agitation.
- psychopathic disorder — (in England, according to the Mental Health Act 1983) a persistent disorder or disability of mind which results in abnormally aggressive or seriously irresponsible conduct on the part of the person concerned
- psychopharmacotherapy — the use of psychoactive drugs in the symptomatic treatment or control of mental disorders or psychiatric disease.
- public administration — the implementation of public policy, largely by the executive branch.
- public transportation — means of fare-paying travel
- pulmonary circulation — the circulation of blood from the heart to the lungs for oxygenation and back to the heart.
- pulse code modulation — a form of modulation that transforms a wave-form, as an audio signal, into a binary signal in which information is conveyed by a coded order of pulses for transmission, storage on a disk, or processing by a computer. Abbreviation: PCM.
- pulse-code modulation — a form of modulation that transforms a wave-form, as an audio signal, into a binary signal in which information is conveyed by a coded order of pulses for transmission, storage on a disk, or processing by a computer. Abbreviation: PCM.
- push the panic button — an alarm button for use in an emergency, as to summon help.
- put someone's back up — to annoy someone
- quadralay corporation — (company) The developers of GWHIS. Telephone: +1 512-346-9199. Fax: +1 512-346-8990.
- quasi-socialistically — of or relating to socialists or socialism.
- racial discrimination — prejudice based on race
- radius of convergence — a positive number so related to a given power series that the power series converges for every number whose absolute value is less than this particular number.
- range of significance — the set of subjects for which a given predicate is intelligible
- rap over the knuckles — to reprimand
- rattle someone's cage — to upset or anger someone
- reading comprehension — a text that students use to help them improve their reading skills, by reading it and answering questions relating to the text. Sometimes used as a test or examination of reading skills. A reading comprehension can be in the student's own or another language
- reciprocal inhibition — the theory that the pairing of an anxiety-provoking stimulus with anxiety-reducing reactions will weaken the association between the stimulus and the anxiety.
- recompression chamber — hyperbaric chamber.
- reconnaissance flight — a flight made by an aircraft in order to obtain military information about a particular place
- reconnaissance patrol — a patrol made by soldiers in order to obtain military information about a particular place
- record of achievement — a statement of the personal and educational development of each pupil
- rectangular hyperbola — a hyperbola with perpendicular asymptotes
- red-headed woodpecker — a black and white North American woodpecker, Melanerpes erythrocephalus, having a red head and neck.
- redevelopment company — a private corporation or a public agency that stimulates the improvement of land, as through a building project subject to certain designs and controls, by financing, selling, or leasing such real estate to interested buyers or lessees.
- registration document — a document giving identification details of a motor vehicle, including its manufacturer, date of registration, engine and chassis numbers, and owner's name
- rehabilitation centre — a centre or clinic where people with an alcohol or drug addiction are treated
- reinforcement therapy — a behavior modification technique in which appropriate behavior is strengthened through systematic reinforcement.
- relaxation oscillator — a nonsinusoidal oscillator, the timing of which is controlled by the charge and discharge time constants of resistance and capacitance components
- remote procedure call — (networking, programming) (RPC) A protocol which allows a program running on one host to cause code to be executed on another host without the programmer needing to explicitly code for this. RPC is an easy and popular paradigm for implementing the client-server model of distributed computing. An RPC is initiated by the caller (client) sending request message to a remote system (the server) to execute a certain procedure using arguments supplied. A result message is returned to the caller. There are many variations and subtleties in various implementations, resulting in a variety of different (incompatible) RPC protocols.
- replacement algorithm — The method used to determine which entry in an associative cache to flush to main memory when it is desired to cache a new block of data. The "least recently used" algorithm flushed the block which has not been accessed for the longest time. A random replacement algorithm picks any block with equal probability.
- retarded acceleration — velocity increase constrained by opposing forces such as wind resistance or braking
- reverberation chamber — a room with walls that reflect sound. It is used to make acoustic measurements and as a source of reverberant sound to be mixed with direct sound for recording or broadcasting
- reverberatory furnace — See at reverberatory (def 2).
- richard coeur de lion — ("Richard the Lion-Hearted"; "Richard Coeur de Lion") 1157–99, king of England 1189–99.
- ring down the curtain — to lower the curtain at the end of a theatrical performance
- road traffic accident — an accident involving vehicles
- rocky mountain locust — a migratory locust, Melanoplus spretus, that occurs in North America, especially the Great Plains, where swarms cause great damage to crops and other vegetation.
- rocky mountain oyster — mountain oyster.
- roman catholic church — the Christian church of which the pope, or bishop of Rome, is the supreme head.
- royal victorian order — (in Britain) an order of chivalry founded by Queen Victoria in 1896, membership of which is conferred for special services to the sovereign
- rutherford scattering — the scattering of an alpha particle through a large angle with respect to the original direction of motion of the particle, caused by an atom (Rutherford atom) with most of the mass and all of the positive electric charge concentrated at a center or nucleus.