18-letter words containing a, t, s
- status epilepticus — a condition in which repeated epileptic seizures occur without the patient gaining consciousness between them. If untreated for a prolonged period it can lead to long-term disability or death
- statutory sick pay — the pay an employee is legally entitled to when sick
- steller's sea lion — any of several large eared seals, as Eumetopias jubatus (Steller's sea lion) of the northern Pacific, and Zalophus californicus (California sea lion) of the Pacific coast of North America.
- stem-cell research — research that is carried out on stem cells for use in medicine
- stepping-off place — jumping-off place (def 2).
- stinking chamomile — mayweed.
- stirling's formula — a relation that approximates the value of n factorial (n!), expressed as .
- stoichiometrically — of or relating to stoichiometry.
- stokely carmichael — Hoagland Howard [hohg-luh nd] /ˈhoʊg lənd/ (Show IPA), ("Hoagy") 1899–1981, U.S. songwriter and musician.
- stomach sweetbread — sweetbread (def 1).
- store launch event — A store launch event is a special event, which publicizes the opening of a new store and at which discounts and free samples may be offered.
- strait of magellan — a strait between the mainland of S South America and Tierra del Fuego, linking the S Pacific with the S Atlantic. Length: 600 km (370 miles). Width: up to 32 km (20 miles)
- straits of florida — a sea passage between the Florida Keys and Cuba, linking the Atlantic with the Gulf of Mexico
- strangeness number — a quantum number, designating the strangeness of an elementary particle, equivalent to the hypercharge minus the baryon number
- strathclyde region — a former local government region in W Scotland: formed in 1975 from Glasgow, Renfrewshire, Lanarkshire, Buteshire, Dunbartonshire, and parts of Argyllshire, Ayrshire, and Stirlingshire; replaced in 1996 by the council areas of Glasgow, Renfrewshire, East Renfrewshire, Inverclyde, North Lanarkshire, South Lanarkshire, Argyll and Bute, East Dunbartonshire, West Dunbartonshire, North Ayrshire, South Ayrshire, and East Ayrshire
- stratigraphic trap — A stratigraphic trap is a rock formation that contains hydrocarbons and is sealed by other rock formations.
- street certificate — a certificate showing ownership of a specified number of shares of stock: endorsed by the owner and guaranteed by a broker, it may be traded without formal transfer on the books of the corporation issuing the stock.
- strike an attitude — to assume a posture or pose, often an affected or theatrical one
- strong interaction — the interaction between gluons and between gluons and quarks that is responsible for the strong force.
- stroustrup, bjarne — Bjarne Stroustrup
- structural formula — a chemical formula showing the linkage of the atoms in a molecule diagrammatically, as H–O–H.
- structural geology — the branch of geology dealing with the structure and distribution of the rocks that make up the crust of the earth. Also called tectonics. Compare structure (def 7a).
- study hall teacher — a teacher who supervises or helps students during a period of time or lesson used for studying
- sturt's desert pea — the desert pea
- sub-classification — to arrange in subclasses.
- subatomic particle — physics:
- subordinate clause — a clause that modifies the principal clause or some part of it or that serves a noun function in the principal clause, as when she arrived in the sentence I was there when she arrived or that she has arrived in the sentence I doubt that she has arrived.
- subsistence farmer — a farmer who consumes most of the produce he grows, leaving little or nothing to be marketed
- substitute teacher — educator: replaces sb temporarily
- sugarloaf mountain — a mountain in SE Brazil in Rio de Janeiro, at the entrance to Guanabara Bay. 1280 feet (390 meters).
- sun-dried tomatoes — tomatoes that have been dried or preserved by exposure to the sun
- super giant slalom — a slalom race in which the course is longer and has more widely spaced gates than in a giant slalom.
- super royal octavo — a book size, 63⁄4 by 101⁄4 inches
- super royal quarto — a book size, 101⁄4 by 131⁄2 inches
- supporting actress — an actress playing a supporting role
- supportive therapy — any treatment, such as the intravenous administration of certain fluids, designed to reinforce or sustain the physiological well-being of a patient
- supraorbital ridge — browridge.
- surface-to-surface — (of a missile, message, etc.) capable of traveling from a base on the surface of the earth to a target also on the surface.
- sustaining program — a radio or television program without a commercial sponsor.
- sutton-in-ashfield — a market town in N central England, in W Nottinghamshire. Pop: 41 951 (2001)
- swarm intelligence — the collective behaviour of a group of animals, esp social insects such as ants, bees, and termites, that are each following very basic rules
- swartkrans ape-man — the fossil remains of the extinct hominid Australopithecus robustus, found at Swartkrans, Republic of South Africa: formerly classified in the genus Paranthropus.
- swedish gymnastics — a system of passive and active exercising of muscles and joints
- sweet vernal grass — a Eurasian meadow grass, Anthoxanthum odoratum, found throughout North America, having clusters of brownish-green flowers.
- sweptwing aircraft — an aircraft which has wings that are swept (usually) backwards
- sympathetic strike — sympathy strike.
- sympathetic string — a thin wire string, as in various obsolete musical instruments, designed to vibrate sympathetically with the bowed or plucked strings to reinforce the sound.
- symphony orchestra — a large orchestra composed of wind, string, and percussion instruments and organized to perform symphonic compositions.
- system-programming — a program, as an operating system, compiler, or utility program, that controls some aspect of the operation of a computer (opposed to application program).
- systematic phoneme — a phonological unit in generative phonology representing an underlying form that takes into account the relationship between phonological patterns and morphological variation, as the unit underlying the second vowel in both derive and derivative.