21-letter words containing a, l, s, t, o
- reconnaissance flight — a flight made by an aircraft in order to obtain military information about a particular place
- reconnaissance patrol — a patrol made by soldiers in order to obtain military information about a particular place
- relaxation oscillator — a nonsinusoidal oscillator, the timing of which is controlled by the charge and discharge time constants of resistance and capacitance components
- residual unemployment — the unemployment that remains in periods of full employment, as a result of those mentally, physically, or emotionally unfit to work
- rest on one's laurels — Also called bay, sweet bay. a small European evergreen tree, Laurus nobilis, of the laurel family, having dark, glossy green leaves. Compare laurel family.
- reverse polish syntax — postfix notation
- rocky mountain locust — a migratory locust, Melanoplus spretus, that occurs in North America, especially the Great Plains, where swarms cause great damage to crops and other vegetation.
- rolling in the aisles — (of an audience) overcome with laughter
- safe in the knowledge — If you do something safe in the knowledge that something else is the case, you do the first thing confidently because you are sure of the second thing.
- saint elias mountains — a mountain range between SE Alaska and the SW Yukon, Canada. Highest peak: Mount Logan, 5959 m (19 550 ft)
- salam-weinberg theory — the electroweak theory.
- sampling distribution — the distribution of a statistic based on all possible random samples that can be drawn from a given population.
- san gabriel mountains — a mountain range in S California, N of Los Angeles. Highest peak, San Antonio Peak, 10,080 feet (3072 meters).
- 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.
- scarlet monkey flower — any of various plants belonging to the genus Mimulus, of the figwort family, as M. cardinalis (scarlet monkey flower) having spotted flowers that resemble a face.
- 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)
- scintillation counter — a device for detecting and measuring radioactivity, having a crystal scintillator, a photoelectric cell sensitive to the light from scintillations, and an amplifier.
- 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.
- secure hash algorithm —
- self-characterization — portrayal; description: the actor's characterization of a politician.
- sentential connective — any of several words or their equivalent symbols used in logical formulas to connect propositions, as “or,” “not,” “and,” “if and only if.”.
- sequoia national park — a national park in central California: giant sequoia trees. 604 sq. mi. (1565 sq. km).
- settle someone's hash — a dish of diced or chopped meat and often vegetables, as of leftover corned beef or veal and potatoes, sautéed in a frying pan or of meat, potatoes, and carrots cooked together in gravy.
- seventeen-year locust — a cicada, Magicicada septendecim, of the eastern U.S., having nymphs that live in the soil, usually emerging in great numbers after 17 years in the North or 13 years in the South.
- sierra madre oriental — the system of mountains in the east of Mexico
- signal-to-noise ratio — the ratio of one parameter, such as power of a wanted signal to the same parameter of the noise at a specified point in an electronic circuit, etc
- silicon tetrachloride — a colorless, fuming liquid, SiCl 4 , used chiefly for making smoke screens and various derivatives of silicon.
- silicon tetrafluoride — a colorless, fuming gas, SiF 4 , used chiefly in the manufacture of fluosilicic acid.
- 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.
- skeleton at the feast — a person or event that brings gloom or sadness to an occasion of joy or celebration
- social administration — the administration and maintenance of issues to do with social policies and welfare
- 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
- social stratification — the act or an instance of stratifying.
- 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
- sovereign wealth fund — an investment fund created using the financial assets of a national government
- 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.
- 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.