ex·traor·di·nar·y / ikˈstrôrdnˌerē; ˌekstrəˈôrdn-/ • adj. very unusual or remarkable: the extraordinary plumage of the male. ∎  unusually great: young children need extraordinary amounts of attention. ∎  (of a meeting) specially convened: an extraordinary session of the Congress. ∎  (of an official) additional; specially employed: his appointment as Ambassador Extraordinary in London.• n. (usu. extraordinaries) an item in a company's accounts not arising from its normal activities. DERIVATIVES: ex·traor·di·nar·i·ly / -ˌerəlē/ adv. ex·traor·di·nar·i·ness n.

extraordinary that is out of the usual course XV; exceptional XVI. — L. extrāordinārius, f. phr. extrā ordinem out of course, in an unusual manner; see EXTRA-, ORDINARY.