21-letter words containing p, l, o, i
- 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).
- simple actor language — (language) (SAL) A minimal actor language, used for teaching in:
- 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.
- 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.
- spotted alfalfa aphid — a pale yellowish aphid, Therioaphis maculata, of the southern U.S., especially west of the Mississippi River, that is marked with black spots and has fine spines on its back: a pest mainly of alfalfa and some other legumes, as clover.
- 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.
- subjective complement — subject complement.
- 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.
- supply-side economics — a school of economic thought that emphasizes the importance to a strong economy of policies that remove impediments to supply
- terrestrial telescope — a refracting telescope having inverting lenses or an eyepiece that presents an erect image.
- the antipodes islands — a group of small uninhabited islands in the South Pacific, southeast of and belonging to New Zealand. Area: 62 sq km (24 sq miles)
- the central provinces — the Canadian provinces of Ontario and Quebec
- the oldest profession — prostitution
- 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.
- thermal power station — a power station in which heat is converted into electricity
- thermoelectric couple — thermocouple.
- threshold wage policy — a policy whereby wages are increased in accordance with inflation
- to be a hospital case — if you say that someone or something is a hospital case, you mean that they need urgent help because they are doing very badly
- to be public property — to be publicly owned
- to blow sth wide open — to expose something
- to fall into the trap — If someone falls into the trap of doing something, they think or behave in a way which is not wise or sensible.
- to play second fiddle — If you play second fiddle to someone, your position is less important than theirs in something that you are doing together.
- topological invariant — a property of a topological space that is a property of every space related to the given space by a homeomorphism.
- traveling salesperson — a representative of a business firm who travels in an assigned territory soliciting orders for a company's services.
- triple superphosphate — superphosphate (def 2).
- triple-superphosphate — Also called acid phosphate. a mixture of calcium acid phosphate and calcium sulfate prepared by treating phosphate rock with sulfuric acid: used chiefly as a fertilizer.