21-letter words containing s, p, l, i
- public administration — the implementation of public policy, largely by the executive branch.
- public health service — the agency that is responsible for the health of the general public
- public transportation — means of fare-paying travel
- 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.
- 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 height analyser — a multichannel analyser that sorts pulses into selected amplitude ranges
- pulse height analyzer — an instrument that records or counts an electrical pulse if its amplitude falls within specified limits: used in nuclear physics research for the determination of energy spectra of nuclear radiations
- 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-time modulation — radio transmission in which the carrier is modulated to produce a series of pulses timed to transmit the amplitude and pitch of a signal. Abbr.: PTM.
- 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.
- ralph roister doister — a play (1553?) by Nicholas Udall: the earliest known English comedy.
- real operating system — (operating system, abuse) The sort the speaker is used to. People from the BSDophilic academic community are likely to issue comments like "System V? Why don't you use a *real* operating system?", people from the commercial/industrial Unix sector are known to complain "BSD? Why don't you use a *real* operating system?", and people from IBM object "Unix? Why don't you use a *real* operating system?" See holy wars, religious issues, proprietary, Get a real computer!.
- reconnaissance patrol — a patrol made by soldiers in order to obtain military information about a particular place
- residual unemployment — the unemployment that remains in periods of full employment, as a result of those mentally, physically, or emotionally unfit to work
- reverse polish syntax — postfix notation
- roll with the punches — a thrusting blow, especially with the fist.
- roll-on-roll-off ship — a cargo ship or ferry designed so that vehicles can be driven straight on and straight off
- sales finance company — a finance company that purchases, at a discount, installment contracts from dealers or that finances retail sales.
- sampling distribution — the distribution of a statistic based on all possible random samples that can be drawn from a given population.
- scalar multiplication — an operation used in the definition of a vector space in which the product of a scalar and a vector is a vector, the operation is distributive over the addition of both scalars and vectors, and is associative with multiplication of scalars
- 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
- scholastic philosophy — the system of philosophy, theology, and teaching that dominated medieval western Europe and was based on the writings of the Church Fathers and (from the 12th century) Aristotle, the Greek philosopher (384–322 bc)
- 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.
- sequoia national park — a national park in central California: giant sequoia trees. 604 sq. mi. (1565 sq. km).
- seven-segment display — (electronics) (SSD) A kind of display element consisting of seven independently controllable lines arranged as a rectangular figure eight. A seven-segment display is the simplest device that can display any of the digits zero to nine (and some other characters) by lighting different combinations of lines. They are often seen in electronic calculators or measuring equipment.
- simple actor language — (language) (SAL) A minimal actor language, used for teaching in:
- single parent benefit — a form of government funded financial assistance paid to single parents
- single spanish burton — a tackle having a runner as well as the fall supporting the load, giving a mechanical advantage of three, neglecting friction.
- 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.
- sleep-terror disorder — night terror.
- social anthropologist — an anthropologist who deals with cultural and social phenomena such as kinship systems or beliefs, esp of nonliterate peoples
- 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
- socialist labor party — a U.S. political party, organized in 1874, advocating the peaceful introduction of socialism.
- sodium metabisulphite — an inorganic compound with the chemical formula Na2S2O5 that is used as a preservative, antioxidant and disinfectant
- 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.
- spicebush swallowtail — a swallowtail butterfly, Papilio troilus, having a dark body with yellow spots on the forewings and greenish hind wings.
- spin angular momentum — to make (yarn) by drawing out, twisting, and winding fibers: Pioneer women spun yarn on spinning wheels.
- splice the main brace — to join together or unite (two ropes or parts of a rope) by the interweaving of strands.
- split-finger fastball — a type of fastball that sinks abruptly as it nears home plate, thrown with the grip used for a forkball
- 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.