21-letter words containing m, u, y
- virtual memory system — (operating system) (VMS) DEC's proprietary operating system originally produced for its VAX minicomputer. VMS V1 was released in August 1978. VMS was renamed "OpenVMS" around version 5.5. The first version of VMS on DEC Alpha was known as OpenVMS for AXP V1.0, and the correct way to refer to the operating system now is OpenVMS for VAX or OpenVMS for Alpha. The renaming also signified the fact that the X/Open consortium had certified OpenVMS as having a high support for POSIX standards. VMS is one of the most secure operating systems on the market (making it popular in financial institutions). It currently (October 1997) has the best clustering capability (both number and distance) and is very scalable with binaries portable from small desktop workstations up to huge mainframes. Many Unix fans generously concede that VMS would probably be the hacker's favourite commercial OS if Unix didn't exist; though true, this makes VMS fans furious.
- 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
- water-vascular system — a system of closed, fluid-filled tubes and ducts of echinoderms used in clinging, locomotion, feeding, and respiration.
- william of malmesbury — William of, William of Malmesbury.
- yellow mercuric oxide — a slightly crystalline, water-soluble, poisonous compound, HgO, occurring as a coarse, orange-red powder (red mercuric oxide) or as a fine, orange-yellow powder (yellow mercuric oxide) used chiefly as a pigment in paints and as an antiseptic in pharmaceuticals.
- yellow-fever mosquito — a mosquito, Aedes aegypti, that transmits yellow fever and dengue.
- yellow-rumped warbler — a common North American wood warbler, Dendroica coronata, having yellow spots on the rump, crown, and sides, including a white-throated eastern subspecies (myrtle warbler) and a yellow-throated western subspecies (Audubon's warbler)
- your mileage may vary — (jargon) (YMMV) The disclaimer American car manufacturers attached to EPA mileage ratings. A humourous way of saying that the thing under discussion will not necessarily give you the same results as the author. Often used to convey the hardware dependence of Unix freeware distributions.
- youth training scheme — (formerly, in Britain) a scheme, run by the Training Agency, to provide vocational training for unemployed 16–17-year-olds