20-letter words containing a, i, o
- shake in one's shoes — to tremble with fear or apprehension
- shank of the evening — the latter part of the afternoon
- shareholders' equity — Shareholders' equity is the total amount of ownership investment in a company.
- sharp-tailed sparrow — a sparrow, Ammospiza caudacuta, inhabiting salt marshes in North America, having narrow, sharply pointed tail feathers.
- shear transformation — a map of a coordinate space in which one coordinate is held fixed and the other coordinate or coordinates are shifted.
- shifting cultivation — a land-use system, esp in tropical Africa, in which a tract of land is cultivated until its fertility diminishes, when it is abandoned until this is restored naturally
- short back and sides — If a man has a short back and sides, his hair is cut very short at the back and sides with slightly thicker, longer hair on the top of the head.
- shoulder-length hair — hair that reaches a person's shoulders
- silicon tetrahydride — silane (def 1).
- sinfonia concertante — a type of concerto for two or more solo instruments accompanied by an orchestra
- skating championship — a competition for ice-skating
- slow-scan television — a technique or system in which an image is scanned electronically more slowly than is normally done in order to produce images, especially of still pictures, that can be transmitted economically, as over a telephone line, and displayed on a television screen.
- small craft advisory — a U.S. National Weather Service advisory of sustained winds, over coastal and inland waters, with speeds of 20–33 knots (23–38 mph, 10–17 m/sec). Regional NWS offices have discretion over the choice of the lower limit.
- snow-on-the-mountain — a North American euphorbiaceous plant, Euphorbia marginata, having white-edged leaves and showy white bracts surrounding small flowers
- snowflake generation — the generation of people who became adults in the 2010s, viewed as being less resilient and more prone to taking offence than previous generations
- snows of kilimanjaro — a short story (1936) by Ernest Hemingway.
- social security card — a card that contains details of a person's social security number
- societal development — the formation and transformation of social life, customs, institutions, etc.
- sodium fluoroacetate — a white, amorphous, water-soluble, poisonous powder, C 2 H 2 FO 2 Na, used as a rodenticide.
- sodium meta-arsenite — sodium arsenite.
- sodium metabisulfite — Sodium metabisulfite is a crystalline compound used as an antioxidant.
- soft gelatin capsule — A soft gelatin capsule is a type of capsule that is usually used to contain medicine in the form of liquid or powder, and which dissolves more quickly than a hard gelatin capsule.
- software engineering — the process of writing computer programs
- solitary confinement — the confinement of a prisoner in a cell or other place in which he or she is completely isolated from others.
- sound-and-light show — a nighttime spectacle or performance, at which a building, historic site, etc., is illuminated and the historic significance is imparted to spectators by means of narration, sound effects, and music.
- south american plate — a major tectonic division of the earth's crust, comprising the continent of South America and several ocean basins and bounded on the north by the Caribbean Plate, on the east by the Mid-Atlantic Ridge, on the west by a submarine trench that borders the western coast of the continent, and on the south by the Antarctic Plate.
- south atlantic ocean — the part of the Atlantic Ocean extending S from the Equator to the Antarctic continent.
- south orkney islands — an uninhabited group of islands in the S Atlantic, southeast of Cape Horn: formerly a dependency of the Falkland Islands; part of the British Antarctic Territory since 1962 (claims are suspended under the Antarctic Treaty). Area: 621 sq km (240 sq miles)
- southern oscillation — a low-latitude fluctuation of atmospheric pressure closely linked with El Niño events, specifically the periods of El Niño warming and La Niña cooling.
- space-time continuum — Also called space-time continuum. the four-dimensional continuum, having three spatial coordinates and one temporal coordinate, in which all physical quantities may be located.
- span of apprehension — the maximum number of objects that can be correctly assessed after a brief presentation
- spanish oyster plant — a composite plant, Scolymus hispanicus, of southern Europe, having spiny, thistlelike leaf margins, small yellow flowers, and an edible root.
- spatial technologies — (company) Distributors of the ACIS solid modelling engine.
- special boat service — a unit of the Royal Marines specializing in reconnaissance and sabotage
- special patrol group — a former police unit tasked with counter terrorism in the Royal Ulster Constabulary
- special relationship — the exceptionally close political, diplomatic, cultural and historical relations between the United States and the United Kingdom
- specific conductance — conductivity (def 2).
- specific performance — (especially in the sale of land) literal compliance with one's contractual promises pursuant to a judicial mandate.
- specific-conductance — conductivity (def 2).
- spectroscopic binary — a binary star having components that are not sufficiently separated to be resolved by a telescope, known to be a binary only bythe variations in wavelength of emitted light that are detected by a spectroscope.
- spherical aberration — variation in focal length of a lens or mirror from center to edge, due to its spherical shape.
- spherical coordinate — 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.
- spiral of archimedes — a curve that is the locus of a point that moves outward with uniform speed along a vector, beginning at the origin, while the vector rotates about the origin with uniform angular velocity. Equation (in polar coordinates): r = aθ.
- spirits of hartshorn — a colorless, pungent, suffocating, aqueous solution of about 28.5 percent ammonia gas: used chiefly as a detergent, for removing stains and extracting certain vegetable coloring agents, and in the manufacture of ammonium salts.
- spontaneous abortion — miscarriage (def 1).
- spontaneous-abortion — Also called voluntary abortion. the removal of an embryo or fetus from the uterus in order to end a pregnancy.
- spotted crane's-bill — the American wild geranium, Geranium maculatum.
- square cross-section — If a kelly has a square cross-section, it has a surface area with four equal sides, when looked at as if has been sliced through.
- square of opposition — a diagrammatic representation of the opposition of categorical propositions.
- squatter sovereignty — (used contemptuously by its opponents) popular sovereignty (def 2).