21-letter words containing s, l, a
- 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 of hard knocks — the experience gained from living, especially from disappointment and hard work, regarded as a means of education: The only school he ever attended was the school of hard knocks.
- 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.
- sealed-beam headlight — a headlight in which the reflector and lens are hermetically sealed together with the filament in a single unit.
- secure hash algorithm —
- self-characterization — portrayal; description: the actor's characterization of a politician.
- semantic differential — a technique for measuring the connotative meaning of concepts by having an individual rate each concept on a series of graduated scales, each scale defined by a pair of polar adjectives, as good–bad or strong–weak.
- sense and sensibility — a novel (1811) by Jane Austen.
- 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.
- 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.
- 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.
- share and share alike — with each having an equal share
- 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 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.
- sir william alexander — Sir William (Alexander) 1867–1957, Scottish lexicographer and philologist.
- siren call/siren song — A siren call or siren song is the appeal that something has although it is harmful or dangerous.
- skeleton at the feast — a person or event that brings gloom or sadness to an occasion of joy or celebration
- slatwall merchandiser — A slatwall merchandiser is a three-dimensional display unit with grooves cut into its surface into which metal hanging rails can be fixed at various heights.
- 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.
- 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
- 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.
- stained glass ceiling — a situation in a church organization in which promotion for a female member of the clergy appears to be possible, but discrimination prevents it
- statistical inference — the theory, methods, and practice of forming judgments about the parameters of a population, usually on the basis of random sampling
- statistical mechanics — the science that deals with average properties of the molecules, atoms, or elementary particles in random motion in a system of many such particles and relates these properties to the thermodynamic and other macroscopic properties of the system.