21-letter words containing r, e, l, n, t, m
- tubercular meningitis — an infection of the membranes of the central nervous system caused by the bacterium Mycobacterium tuberculosis; features can include fever, headache, and coma
- twenty-two metre line — one of two lines on a rugby pitch which are twenty-two metres from the goal-line
- ultraviolet astronomy — the branch of astronomy that deals with celestial objects emitting electromagnetic radiation in the ultraviolet range.
- universal affirmative — a proposition of the form “All S is P.” Symbol: A, a.
- 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.
- 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
- voluntary arrangement — a procedure enabling an insolvent company to come to an arrangement with its creditors and resolve its financial problems, often in compliance with a court order
- 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.
- 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.
- worth someone's while — worth someone's time, consideration, etc.; profitable in some way
- xilinx netlist format — (language, electronics) (XNF) A Hardware Description Language for electronic circuit design, developed by Xilinx, Inc..