19-letter words containing c, e, l, o
- preproduction trial — a trial to test a prototype of a product before the product goes into full-scale production
- pride-of-california — a shrubby plant, Lathyrus splendens, of the legume family, native to southern California, having showy clusters of pale rose-pink, violet, or magenta flowers and large, smooth, beaked pods.
- priority scheduling — (operating system) Processes scheduling in which the scheduler selects tasks to run based on their priority as opposed to, say, a simple round-robin. Priorities may be static or dynamic. Static priorities are assigned at the time of creation, while dynamic priorities are based on the processes' behaviour while in the system. For example, the scheduler may favour I/O-intensive tasks so that expensive requests can be issued as early as possible. A danger of priority scheduling is starvation, in which processes with lower priorities are not given the opportunity to run. In order to avoid starvation, in preemptive scheduling, the priority of a process is gradually reduced while it is running. Eventually, the priority of the running process will no longer be the highest, and the next process will start running. This method is called aging.
- prismatic telescope — a telescope having an eyepiece at the side or top equipped with a reflecting prism, used for taking sights at steep angles.
- 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.
- 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
- pseudo-biographical — of or relating to a person's life: He's gathering biographical data for his book on Milton.
- pseudo-hieroglyphic — noting or pertaining to a script dating from the second millennium b.c. that appears to be syllabic and to represent the Phoenician language and that is inscribed on objects found at Byblos.
- pseudo-intellectual — a person exhibiting intellectual pretensions that have no basis in sound scholarship.
- pseudopsychological — of or relating to psychology.
- psychoendocrinology — the study of the relationship between the endocrine system and various symptoms or types of mental illness.
- psychological novel — a novel that focuses on the complex mental and emotional lives of its characters and explores the various levels of mental activity.
- 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
- pull one's socks up — to make a determined effort, esp in order to regain control of a situation
- quantum electronics — the application of quantum mechanics and quantum optics to the study and design of electronic devices
- radioactive fallout — the settling to the ground of airborne particles ejected into the atmosphere from the earth by explosions, eruptions, forest fires, etc., especially such settling from nuclear explosions (radioactive fallout) Compare rainout.
- radiopharmaceutical — any of a number of radioactive drugs used diagnostically or therapeutically.
- 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.
- rake over the coals — a black or dark-brown combustible mineral substance consisting of carbonized vegetable matter, used as a fuel. Compare anthracite, bituminous coal, lignite.
- rancho palos verdes — a town in SW California.
- rap on the knuckles — a mild reprimand or light sentence
- rec room (or hall) — recreation room (or hall)
- recessional moraine — a moraine marking a temporary halt in the general retreat of a glacier.
- reciprocal exchange — an unincorporated association formed so that its members can participate in reciprocal insurance.
- reciprocal leveling — leveling between two widely separated points in which observations are made in both directions to eliminate the effects of atmospheric refraction and the curvature of the earth.
- reciprocity failure — a failure of the two exposure variables, light intensity and exposure time, to behave in a reciprocal fashion at very high or very low values
- 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.
- reference electrode — an electrode of known oxidation potential used in determining the electromotive force of a galvanic cell.
- register allocation — (compiler, algorithm) The phase of a compiler that determines which values will be placed in registers. Register allocation may be combined with register assignment. This problem can be shown to be isomorphic to graph colouring by relating values to nodes in the graph and registers to colours. Values (nodes) which must be valid simultaneously are linked by edges and cannot be stored in the same register (coloured the same). See also register dancing and register spilling.
- regular icosahedron — an icosahedron in which each of the faces is an equilateral triangle
- 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.
- relative complement — the set of elements contained in a given set that are not elements of another specified set.
- religious education — religion as school subject
- relocation expenses — Relocation expenses are a sum of money that a company pays to someone who moves to a new area in order to work for the company. The money is to help them pay for moving house.
- removable cartridge — a hard disk enclosed in a case that can be removed from the disk drive, having more storage than floppy disks.
- 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 letters — the collective body of literary people.
- 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
- research fellowship — the position or office of someone who conducts academic research into a subject at a university, etc
- research laboratory — place for scientific experimentation
- resorcinolphthalein — fluorescein.
- 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.
- reversible reaction — a reaction that, depending on ambient conditions, can proceed in either of two directions: the production of the reaction products from the reactants, or the production of the original reactants from the formed reaction products. Compare equilibrium (def 4).
- 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?”.