21-letter words containing p, e, r, l, c
- 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.
- projection television — a television picture display system consisting of a special receiver and an optical system that projects an enlarged picture on a screen.
- protective coloration — coloration or anything likened to it that eliminates or reduces visibility or conspicuousness.
- 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.
- psychoneuroimmunology — the study of the effects of psychological factors on the immune system
- public address system — loudspeaker
- public health service — the agency that is responsible for the health of the general public
- public-address system — a combination of electronic devices that makes sound audible via loudspeakers to many people, as in an auditorium or out of doors.
- public-key encryption — (cryptography) (PKE, Or "public-key cryptography") An encryption scheme, introduced by Diffie and Hellman in 1976, where each person gets a pair of keys, called the public key and the private key. Each person's public key is published while the private key is kept secret. Messages are encrypted using the intended recipient's public key and can only be decrypted using his private key. This is often used in conjunction with a digital signature. The need for sender and receiver to share secret information (keys) via some secure channel is eliminated: all communications involve only public keys, and no private key is ever transmitted or shared. Public-key encryption can be used for authentication, confidentiality, integrity and non-repudiation. See also knapsack problem.
- purple-fringed orchid — either of two orchids, Habenaria fimbriata or H. psycodes, of eastern North America, having a cluster of fragrant purple flowers with a fringed lip.
- purple-fringed orchis — either of two North American orchids (Habenaria psycodes and H. fimbriata) with purple-fringed flowers
- put sb in their place — If you put someone in their place, you show them that they are less important or clever than they think they are.
- rap over the knuckles — to reprimand
- 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.
- reconnaissance patrol — a patrol made by soldiers in order to obtain military information about a particular place
- rectangular hyperbola — a hyperbola with perpendicular asymptotes
- 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.
- 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.
- remote write protocol — (chat, protocol) (RWP) A proposed Internet protocol for exchanging short messages between terminals. The RWP proposal is detailed in RFC 1756.
- 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.
- return the compliment — repay sb's kindness with a kind act
- roll with the punches — a thrusting blow, especially with the fist.
- round-necked pullover — a sweater with a plain round neckline
- scalar triple product — the volume of the parallelepiped defined by three given vectors, u, v, and w, usually represented as u·v 1 (v×w), [ uvw ], or (uvw), where × denotes a cross product and · denotes an inner product.
- schlieren photography — a type of photography which records schlieren
- school superintendent — an official whose job is to oversee school administration within a district
- schoolgirl complexion — a smooth, clear complexion, such as schoolgirls are considered to have
- scorched earth policy — a military practice of devastating the property and agriculture of an area before abandoning it to an advancing enemy.
- scorched-earth policy — a military practice of devastating the property and agriculture of an area before abandoning it to an advancing enemy.
- simple actor language — (language) (SAL) A minimal actor language, used for teaching in:
- sinusoidal projection — an equal-area projection in which parallels are straight lines spaced at regular intervals, the central meridian is a straight line one-half the length of the equator, and the other meridians are curves symmetrical to the central meridian.
- social inquiry report — (in Britain) a report on a person and his or her circumstances, which may be required by a court before sentencing and is made by a probation officer or a social worker from a local authority social services department
- space shuttle orbiter — orbiter (def 1).
- special correspondent — a journalist who covers stories firsthand from a war zone
- special court-martial — a court-martial established to try violations of military law less serious than those tried by a general court-martial but more serious than those tried by a summary court-martial.
- spherical coordinates — Usually, spherical coordinates. any of three coordinates used to locate a point in space by the length of its radius vector and the angles this vector makes with two perpendicular polar planes.
- splice the main brace — to join together or unite (two ropes or parts of a rope) by the interweaving of strands.
- split-screen facility — a facility allowing different scenes to be shown on screen at the same time
- sport utility vehicle — a rugged vehicle with a trucklike chassis and four-wheel drive, designed for occasional off-road use. Abbreviation: SUV.
- sport-utility vehicle — a rugged vehicle with a trucklike chassis and four-wheel drive, designed for occasional off-road use. Abbreviation: SUV.
- stabilization-process — the act or process of stabilizing or the state of being stabilized.
- stock list department — (in an American stock exchange) the department dealing with monitoring compliance with its listing requirements and rules
- stop loss reinsurance — Stop loss reinsurance is a form of reinsurance under which the reinsurer pays the cedant's losses in any year over a particular percentage of the earned premium.
- subliminal perception — perception of or reaction to a stimulus that occurs without awareness or consciousness
- supergranulation cell — one of a number of large convection cells in the photosphere and chromosphere of the sun, each having a diameter of 10,000–20,000 miles (16,000–32,000 km) and lasting longer than a day.
- terrestrial telescope — a refracting telescope having inverting lenses or an eyepiece that presents an erect image.
- the central provinces — the Canadian provinces of Ontario and Quebec
- theoretical physicist — a scientist who studies theoretical physics
- thermal decomposition — Thermal decomposition is the process in which a chemical species breaks down when its temperature is increased.
- thermoelectric couple — thermocouple.