18-letter words containing a, r, o, n, i
- universal coupling — a coupling between rotating shafts set at an angle to one another, allowing for rotation in three planes.
- unix international — (body) (UI) A consortium including Sun, AT&T and others formed to promote an open environment based on Unix System V, including the Open Look windowing system.
- upper partial tone — overtone (def 1).
- urban homesteading — homesteading (def 2).
- vermiform appendix — a narrow, blind tube protruding from the cecum, having no known useful function, in humans being 3 to 4 inches (8 to 10 cm) long and situated in the lower right-hand part of the abdomen.
- veterinary surgeon — Chiefly British. a veterinarian.
- victor emmanuel ii — 1820–78, king of Sardinia 1849–78; first king of Italy 1861–78.
- video surveillance — a system of monitoring activity in an area or building using a television system in which signals are transmitted from a television camera to the receivers by cables or telephone links forming a closed circuit
- virginia snakeroot — any of various plants whose roots have been regarded as a remedy for snakebites, as the herb Aristolochia serpentaria (Virginia snakeroot) having a medicinal rhizome and rootlets, and the white-flowered Polygala senega (Seneca snakeroot) having a medicinal root.
- voluntary abortion — abortion (def 1).
- voluntary-abortion — Also called voluntary abortion. the removal of an embryo or fetus from the uterus in order to end a pregnancy.
- voter registration — the requirement of citizens to become registered in order to vote
- wage determination — the process of setting wage rates or establishing wage structures in particular situations
- wardrobe assistant — a person who assists the wardrobe mistress in a theatre
- warning coloration — a bold, distinctive pattern of color characteristic of a poisonous or unpalatable organism, as the skunk or the monarch butterfly, that functions as a warning to and defense against predators.
- warrant of fitness — a six-monthly certificate required for motor vehicles certifying mechanical soundness
- water of hydration — the portion of a hydrate that is represented as, or can be expelled as, water: now usually regarded as being in true molecular combination with the other atoms of the compound, and not existing in the compound as water.
- water on the brain — hydrocephalus.
- watson-crick model — a widely accepted model for the three-dimensional structure of DNA, featuring a double-helix configuration for the molecule's two hydrogen-bonded complementary polynucleotide strands.
- western alienation — a feeling of resentment by some inhabitants of western Canada against perceived favouritism by the national government towards the eastern provinces
- westinghouse brake — a railroad air brake operated by compressed air.
- wheelchair housing — housing designed or adapted for a chairbound person
- white-faced hornet — any large, stinging paper wasp of the family Vespidae, as Vespa crabro (giant hornet) introduced into the U.S. from Europe, or Vespula maculata (bald-faced hornet or white-faced hornet) of North America.
- wild passionflower — the maypop, Passiflora incarnata.
- wilson's phalarope — a phalarope, Phalaropus tricolor, that breeds in the prairie regions of North America and winters in Argentina and Chile.
- wingback formation — single wingback formation.
- women at point sur — a narrative poem (1927) by Robinson Jeffers.
- women's liberation — a movement to combat sexual discrimination and to gain full legal, economic, vocational, educational, and social rights and opportunities for women, equal to those of men.
- world championship — an international competition in a particular sport or activity for people all around the world
- wrangell mountains — a mountain range in SE Alaska, extending into the Yukon, Canada. Highest peak: Mount Blackburn, 5037 m (16 523 ft)
- writ of assistance — a writ issued by a superior colonial court authorizing officers of the British crown to summon aid and enter and search any premises.
- writ of attachment — a document by which a court orders the seizing of property in order to ensure satisfaction of a judgement
- wrongful dismissal — the act of making someone redundant for reasons which are illegal or unjust
- xenon hexafluoride — a colorless, crystalline compound, XeF 6 , that melts at 50°C to a yellow liquid, and boils at 75°C.
- young conservative — a member of the youth section of the United Kingdom Conservative Party
- zion national park — a park in SW Utah. 148 sq. mi. (383 sq. km).
- zone of saturation — the ground below the water table