21-letter words containing a, c, o, r, u
- student participation — the extent to which students participate or involve themselves in a class, course, etc
- subliminal perception — perception of or reaction to a stimulus that occurs without awareness or consciousness
- substitution reaction — the replacement of an atom or group of atoms in a compound by another atom or group.
- suction and curettage — a technique involving extraction of the fetus through a suction tube, used to perform abortions during the early stages of pregnancy.
- summary court-martial — a court-martial composed of one commissioned officer, authorized to try minor offenses against military law.
- sun protection factor — SPF.
- sunday school teacher — someone who teaches at a Sunday school
- supergranulation cell — one of a number of large convection cells in the photosphere and chromosphere of the sun, each having a diameter of 10,000–20,000 miles (16,000–32,000 km) and lasting longer than a day.
- surface acoustic wave — an acoustic wave generated on the surface of a piezoelectric substrate: used as a filter in electronic circuits
- surface friction drag — the part of the drag on a body moving through a fluid that is dependent on the nature of the surface of the body
- surface of projection — the surface upon which an image or a set of points is projected.
- surface of revolution — a surface formed by revolving a plane curve about a given line.
- surface-to-underwater — (of a missile, message, etc.) traveling from the surface of the earth to a target underwater.
- tartarian honeysuckle — an Asian honeysuckle, Lonicera tatarica, having fragrant, white to pink flowers.
- teleological argument — the argument purporting to prove the existence of God from empirical facts, the premise being that the universe shows evidence of order and hence design
- tenure track position — a position or office that carries with it the opportunity to eventually obtain tenure or the right to permanent employment
- tetrabromofluorescein — eosin (def 1).
- the (norman) conquest — the conquering of England by the Normans under William the Conqueror in 1066
- the household cavalry — a group of British soldiers on horseback who have the job of protecting the king or queen and their family
- therapeutic community — a group-based form of therapy for mental disorders, sometimes residential
- third party procedure — impleader.
- throw sb a curve ball — If someone throws you a curve or throws you a curve ball, they surprise you by doing something that you do not expect.
- throw someone a curve — a continuously bending line, without angles.
- to be hard luck on sb — to be unfortunate or unlucky for someone
- to sink without trace — If you say that someone or something sinks without trace or sinks without a trace, you mean that they stop existing or stop being successful very suddenly and completely.
- trades union congress — The Trades Union Congress in Britain is the same as the TUC.
- tumor necrosis factor — a protein, produced in humans and other animals, that is destructive to cells showing abnormally rapid growth: identical with cachectin. Abbreviation: TNF.
- uniform resource name — (web) (URN, previously Uniform/Universal Resource Number) 1. Any URI which is not a URL. 2. A particular scheme which is currently (1991-4) under development by the IETF, which should provide for the resolution using Internet protocols of names which have a greater persistence than that currently associated with Internet host names or organisations (as used in URLs). Uniform Resource Names will be URI schemes that improve on URLs in reliability over time, including authenticity, replication, and high availability. When defined, a URN in sense 1 will be an example of a URN in sense 2.
- union of south africa — former name for South Africa, Republic of.
- university of iceland — (body, education) The Home of Fjolnir.
- up close and personal — face to face, intimately
- voluntary association — a group of individuals joined together on the basis of mutual interest or common objectives, especially a business group that is not organized or constituted as a legal entity.
- volunteers of america — a religious reform and relief organization, similar to the Salvation Army, founded in New York City in 1896 by Ballington Booth, son of William Booth, the founder of the Salvation Army. Abbreviation: VOA.
- water of constitution — water present in a molecule that cannot be removed without disrupting the molecule.
- william the conqueror — ("the Conqueror") 1027–87, duke of Normandy 1035–87; king of England 1066–87 (son of Robert I, duke of Normandy).
- writ of habeas corpus — law: petition for hearing
- youth training scheme — (formerly, in Britain) a scheme, run by the Training Agency, to provide vocational training for unemployed 16–17-year-olds