21-letter words containing a, c, p, n, o, t
- 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
- sun protection factor — SPF.
- 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 of projection — the surface upon which an image or a set of points is projected.
- sympathetic vibration — a vibration induced by resonance.
- tenure track position — a position or office that carries with it the opportunity to eventually obtain tenure or the right to permanent employment
- the acting profession — actors considered as a group
- the central provinces — the Canadian provinces of Ontario and Quebec
- the joker in the pack — If you describe someone or something as the joker in the pack, you mean that they are different from the other people or things in their group, and can be unpredictable.
- the press association — the national news agency for the United Kingdom and Ireland
- the probation service — a criminal justice service that is mainly responsible for dealing with offenders by placing them under the supervision of a probation officer
- the shipping forecast — a radio broadcast made by the BBC of weather reports and forecasts for the seas around the British Isles
- therapeutic community — a group-based form of therapy for mental disorders, sometimes residential
- thermal decomposition — Thermal decomposition is the process in which a chemical species breaks down when its temperature is increased.
- ticker-tape reception — (mainly in New York) the showering of the motorcade of a distinguished politician, visiting head of state, etc, with ticker tape as a sign of welcome
- to play second fiddle — If you play second fiddle to someone, your position is less important than theirs in something that you are doing together.
- topgallant forecastle — a partial weather deck on top of a forecastle superstructure; forecastle deck.
- topological invariant — a property of a topological space that is a property of every space related to the given space by a homeomorphism.
- what price something? — what are the chances of something happening now?
- white-crowned sparrow — a North American sparrow, Zonotrichia leucophrys, having black and white stripes on the head.
- workers' compensation — a government-sponsored insurance system, funded by contributions from employers, for compensating employees for injury or occupational disease suffered in connection with their employment