18-letter words containing r, e, l, t
- probability theory — the theory of analyzing and making statements concerning the probability of the occurrence of uncertain events. Compare probability (def 4).
- product life cycle — the four stages (introduction, growth, maturity, and decline) into one of which the sales of a product fall during its market life
- property developer — person: deals in real estate
- proprietary colony — any of certain colonies, as Maryland and Pennsylvania, that were granted to an individual or group by the British crown and that were granted full rights of self-government.
- protective colloid — a lyophilic colloid added to a lyophobic sol to lessen its sensitivity to the precipitating effect of an electrolyte.
- protocol converter — (networking) A device or program to translate between different protocols which serve similar functions (e.g. TCP and TP4). Some call this a "gateway", though others use that term for other kinds of internetworking device.
- provascular tissue — procambium.
- pseudotuberculosis — an acute, sometimes fatal disease of rodents, birds, and other animals, including humans, caused by the bacterium Yersinia (Pasteurella) pseudotuberculosis, and characterized by the formation of nodules resembling those that result from tuberculosis.
- psychogalvanometer — a type of galvanometer for detecting and measuring psychogalvanic currents.
- public expenditure — spending by central government, local authorities, and public corporations
- pulmonic airstream — a current of lung air set in motion by the respiratory muscles in the production of speech.
- pulp canal therapy — endodontics.
- purple loosestrife — an Old World plant, Lythrum salicaria, of the loosestrife family, widely naturalized in North America, growing in wet places and having spikes of reddish-purple flowers.
- quality controller — a person responsible for checking that the goods or services produced by an organization are of an acceptable standard
- quality of service — (communications, networking) (QoS) The performance properties of a network service, possibly including throughput, transit delay, priority. Some protocols allow packets or streams to include QoS requirements.
- quarry-tiled floor — a floor covered with square or diamond-shaped unglazed floor tiles
- quarter-wave plate — a crystal thin enough to cause a phase difference of 90° between the ordinary and extraordinary rays of polarized light, thereby converting circularly polarized light into plane polarized light.
- quarterlife crisis — a crisis that may be experienced in one's twenties, involving anxiety over the direction and quality of one's life
- quartz-iodine lamp — a type of tungsten-halogen lamp containing small amounts of iodine and having a quartz envelope, operating at high temperature and producing an intense light for use in car headlamps, etc
- rabbit-foot clover — a plant, Trifolium arvense, having trifoliate leaves with narrow leaflets and fuzzy, cylindrical, grayish-pink flower heads.
- racial segregation — social policy: separation of races
- racially motivated — motivated by (the hate or prejudice of) someone's race
- random walk theory — the theory that the future movement of share prices does not reflect past movements and therefore will not follow a discernible pattern
- range of stability — the angle to the perpendicular through which a vessel may be heeled without losing the ability to right itself.
- rare-earth element — any of a group of closely related metallic elements, comprising the lanthanides, scandium, and yttrium, that are chemically similar by virtue of having the same number of valence electrons.
- rational operation — any of the mathematical operations of addition, subtraction, multiplication, and division.
- rattlesnake master — any of various plants of the genus Eryngium, especially E. yuccifolium, having spiny leaves and dense, rounded flower heads.
- real-estate office — the place where a real-estate agent works
- real-time computer — a computer that can process data or information almost immediately
- rear its ugly head — the upper part of the body in humans, joined to the trunk by the neck, containing the brain, eyes, ears, nose, and mouth.
- red cluster pepper — a tropical, woody plant, Capsicum annuum fasciculatum, having erect, very pungent, red fruit in small clusters.
- red-bellied turtle — any of several freshwater turtles of the genus Pseudemys, of the eastern and southern U.S., having red markings on the lower shell.
- red-light district — an area or district in a city in which many houses of prostitution are located.
- red-spotted purple — any color having components of both red and blue, such as lavender, especially one deep in tone.
- redevelopment area — an urban area in which all or most of the buildings are demolished and rebuilt
- reentering polygon — a polygon having one or more reentering angles.
- reflection density — a measure of the extent to which a surface reflects light or other electromagnetic radiation, equal to the logarithm to base ten of the reciprocal of the reflectance
- refrigerated lorry — a lorry which is chilled in the back as for storing food
- regional enteritis — Crohn's disease.
- registration plate — a plate mounted on the front and back of a motor vehicle bearing the registration number
- regular tertiaries — of the third order, rank, stage, formation, etc.; third.
- reinforced plastic — plastic with fibrous matter, such as carbon fibre, embedded in it to confer additional strength
- reinvent the wheel — (jargon) To design or implement a tool equivalent to an existing one or part of one, with the implication that doing so is silly or a waste of time. This is often a valid criticism. On the other hand, automobiles don't use wooden rollers, and some kinds of wheel have to be reinvented many times before you get them right. On the third hand, people reinventing the wheel do tend to come up with the moral equivalent of a trapezoid with an offset axle.
- relational algebra — (database, theory) A family of algebra with a well-founded semantics used for modelling the data stored in relational databases, and defining queries on it. The main operations of the relational algebra are the set operations (such as union, intersection, and cartesian product), selection (keeping only some lines of a table) and the projection (keeping only some columns). The relational data model describes how the data is structured.
- relative frequency — the ratio of the number of times an event occurs to the number of occasions on which it might occur in the same period.
- relative major key — a major key that has the same key signature as a minor key, but a different tonic
- relative minor key — a minor key that has the same key signature as a major key, but a different tonic
- repayment schedule — a document detailing the specific terms of a borrower's loan, such as monthly payment, interest rate, due dates etc
- replacement engine — an engine used to replace or substitute an older or broken engine (in a vehicle, etc)
- reporters' gallery — an area in parliament reserved for journalists and reporters