21-letter words containing m, n, e, o, i
- ultraviolet astronomy — the branch of astronomy that deals with celestial objects emitting electromagnetic radiation in the ultraviolet range.
- uniform business rate — a local tax in the UK paid by businesses, based on a local valuation of their premises and a rate fixed by central government that applies throughout the country
- 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.
- universal disk format — (storage, standard) (UDF) A CD-ROM file system standard that is required for DVD ROMs. UDF is the OSTA's replacement for the ISO 9660 file system used on CD-ROMs, but will be mostly used on DVD. DVD multimedia disks use UDF to contain MPEG audio and video streams. To read DVDs you need a DVD drive, the kernel driver for the drive, MPEG video support, and a UDF driver. DVDs containing both UDF filesystems and ISO 9660 filesystems can be read without UDF support. UDF can also be used by CD-R and CD-RW recorders in packet writing mode.
- until the end of time — If you say that something will happen or be true until the end of time or to the end of time, you are emphasizing that it will always happen or always be true.
- ventriloquist's dummy — a puppet which is operated by a ventriloquist and made to appear to talk
- vladivostok agreement — a preliminary arms control accord concluded by Soviet leader Leonid Brezhnev and U.S. President Gerald Ford in Vladivostok, U.S.S.R., in December 1974.
- volumetric efficiency — the ratio of fluid delivered by a piston or ram pump per stroke to the displacement volume of the piston or ram
- 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.
- warm silence software — A small company run by(?) Robin Watts, producing software for the Acorn Archimedes.
- weinberg-salam theory — electroweak theory.
- well-ordering theorem — the theorem of set theory that every set can be made a well-ordered set.
- what price something? — what are the chances of something happening now?
- william the conqueror — ("the Conqueror") 1027–87, duke of Normandy 1035–87; king of England 1066–87 (son of Robert I, duke of Normandy).
- wilson's storm petrel — a small petrel, Oceanites oceanicus, that breeds in the Southern Hemisphere but ranges into the North Atlantic and Pacific oceans.
- with sb's compliments — If you say that you are giving someone something with your compliments, you are saying in a polite and fairly formal way that you are giving it to them, especially as a gift or a favour.
- 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
- worth someone's while — worth someone's time, consideration, etc.; profitable in some way
- xeroderma pigmentosum — a rare inherited disease characterized by sensitivity to ultraviolet light, exposure resulting in lesions and tumors of the skin and eyes.
- xilinx netlist format — (language, electronics) (XNF) A Hardware Description Language for electronic circuit design, developed by Xilinx, Inc..
- youth training scheme — (formerly, in Britain) a scheme, run by the Training Agency, to provide vocational training for unemployed 16–17-year-olds
- zero-emission vehicle — a vehicle, as an automobile, that does not directly produce atmospheric pollutants. Abbreviation: ZEV.