16-letter words containing o, a, s, i
- war of secession — American Civil War.
- warminster broom — a European shrub, Cytisus praecox, of the legume family, having yellowish-white or yellow, pealike flowers.
- washington state — the state of Washington, especially as distinguished from Washington, D.C.
- washington thorn — a dense tree, Crataegus phaenopyrum, of the rose family, native to the eastern coast of the U.S., having triangular leaves, small clusters of white flowers, and clusters of bright red fruit.
- washington, d. c — Booker T(aliaferro) [boo k-er tol-uh-ver] /ˈbʊk ər ˈtɒl ə vər/ (Show IPA), 1856–1915, U.S. reformer, educator, author, and lecturer.
- washington, d.c. — Booker T(aliaferro) [boo k-er tol-uh-ver] /ˈbʊk ər ˈtɒl ə vər/ (Show IPA), 1856–1915, U.S. reformer, educator, author, and lecturer.
- weather advisory — advisory (def 5).
- white sandalwood — the fragrant heartwood of any of certain Asian trees of the genus Santalum, used for ornamental carving and burned as incense.
- white wood aster — a composite plant, Aster divaricatus, of North America, having flat-topped clusters of white ray flowers and growing in dry woods.
- whole nine yards — a common unit of linear measure in English-speaking countries, equal to 3 feet or 36 inches, and equivalent to 0.9144 meter.
- wild goose chase — a wild or absurd search for something nonexistent or unobtainable: a wild-goose chase looking for a building long demolished.
- wild-goose chase — a wild or absurd search for something nonexistent or unobtainable: a wild-goose chase looking for a building long demolished.
- wilson's disease — a rare hereditary disease in which copper accumulates in the brain and liver, gradually leading to tremors, muscular rigidity, kidney malfunction, and cognitive disturbances: marked by Kayser-Fleischer rings.
- wilson's warbler — a North American warbler, Wilsonia pusilla, having yellow plumage and a black patch on top of the head.
- windfall profits — Windfall profits are excessive profits with a non-business cause such as a natural disaster.
- windowless monad — (in the philosophy of Leibniz) a monad having no direct causal or perceptual relation with any other monad.
- windowpane shell — capiz.
- wisconsin rapids — a city in central Wisconsin.
- wodzislaw slaski — a city in S Poland.
- woody nightshade — bittersweet (def 3).
- word association — stimulation of an associative pattern by a word.
- world federalism — federalism on a worldwide level.
- world federalist — a promoter or supporter of world federalism.
- writ of subpoena — a legal document commanding the attendance in court, as a witness, of the person on whom it is served, under a penalty
- yah-boo politics — adversarial politics in which politicians constantly deride their opponents and dismiss everything suggested by them
- yeoman's service — good, useful, or workmanlike service: His trusty sword did him yeoman's service.
- zagros mountains — a mountain range in S Iran: has Iran's main oilfields in its W central foothills. Highest peak: Zard Kuh, 4548 m (14 920 ft)
- zygosporangium's — a sporangium that bears a zygospore.