21-letter words containing a, t, s, r
- saint lawrence seaway — a series of channels, locks, and canals between Montreal and the mouth of Lake Ontario, a distance of 182 miles (293 km), enabling most deep-draft vessels to travel from the Atlantic Ocean, up the St. Lawrence River, to all the Great Lakes ports: developed jointly by the U.S. and Canada.
- saint martin's summer — mild, warm weather similar to Indian summer, occurring in November.
- saint-maur-des-fosses — a town in N central France, near Paris, on the Marne River.
- 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).
- san gorgonio mountain — a mountain in S California: highest peak in the San Bernardino Mountains. 11,502 feet (3506 meters).
- sanitation department — the department of local government responsible for collecting and disposing of refuse
- santa barbara islands — group of nine islands, & many islets, off the SW coast of Calif.
- santa cruz water lily — a South American aquatic plant, Victoria cruziana, of the water lily family, having floating leaves from 2–5 feet (0.6–1.5 meters) and deep pink or red flowers.
- sao jose do rio preto — a city in SE Brazil, NW of São Paulo.
- sao tome and principe — Democratic Republic of, a republic in W Africa, comprising the islands of São Tomé and Príncipe, in the Gulf of Guinea, N of the equator: a former overseas province of Portugal; gained independence in 1975. 372 sq. mi. (964 sq. km). Capital: São Tomé.
- saponification number — the number of milligrams of potassium hydroxide required to saponify one gram of a given ester, especially a glyceride.
- satellite dish aerial — a parabolic aerial for reception from or transmission to an artificial satellite
- satisficing behaviour — the form of behaviour demonstrated by firms who seek satisfactory profits and satisfactory growth rather than maximum profits
- 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.
- scarce as hen's teeth — extremely rare
- 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.
- scarlet runner (bean) — a climbing bean plant (Phaseolus coccineus) of tropical America, having pods with large, edible, red-and-black seeds and usually having scarlet flowers: often grown in cold climates as an ornamental
- schlieren photography — a type of photography which records schlieren
- 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.
- secondary containment — Secondary containment is a system for dealing with hazardous spills.
- secure hash algorithm —
- sedimentary sequences — Sedimentary sequences are layers of rock which are derived from weathered rocks, biogenic (= of living organisms) activity, or precipitation from solution.
- seeing/hearing things — If you say that someone is seeing or hearing things, you mean that they believe they are seeing or hearing something that is not really there.
- 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.
- sequoia national park — a national park in central California: giant sequoia trees. 604 sq. mi. (1565 sq. km).
- serbia and montenegro — a former country in SE Europe, consisting of the republics of Serbia and Montenegro; replaced the Federal Republic of Yugoslavia in 2003, and dissolved in 2006 following Montenegro’s decision to secede
- 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.
- sheppard's correction — a method of correcting the bias in standard deviations and higher moments of distributions that arises from grouping values of the variable.
- sherman antitrust act — an act of Congress (1890) prohibiting any contract, conspiracy, or combination of business interests in restraint of foreign or interstate trade.
- short message service — (messaging) (SMS) A message service offered by the GSM digital mobile telephone system. Using SMS, a short alphanumeric message (160 alphanumeric characters) can be sent to a mobile phone to be displayed there, much like in an alphanumeric pager system. The message is buffered by the GSM network until the phone becomes active.
- sierra madre oriental — the system of mountains in the east of Mexico
- sieve of eratosthenes — a method of obtaining prime numbers by sifting out the composite numbers from the set of natural numbers so that only prime numbers remain.
- 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:
- sing a different tune — a succession of musical sounds forming an air or melody, with or without the harmony accompanying it.
- 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.
- skew symmetric matrix — a matrix that is equal to the negation of its transpose
- 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.
- snap one's fingers at — any of the terminal members of the hand, especially one other than the thumb.
- snr bandwidth product — (communications) The integral of the SNR over frequency. The SNR bandwidth product is an important limit in the capacity of a communication channel.