n. (US theater) 1 a a building or outdoor area for dramatic performances. b a cinema. 2 a the writing and production of plays. b effective material for the stage (makes good theatre). 3 a room or hall for lectures etc. with seats in tiers. 4 Brit. an operating theatre. 5 a a scene or field of action (the theatre of war). b (attrib.) designating weapons intermediate between tactical and strategic (theatre nuclear missiles). 6 a natural land-formation in a gradually rising part-circle like ancient Greek and Roman theatres. theatre-goer a frequenter of theatres. theatre-going frequenting theatres. theatre-in-the-round a dramatic performance on a stage surrounded by spectators. theatre sister a nurse supervising the nursing team in an operating theatre.
[ ME f. OF t(h)eatre or f. L theatrum f. Gk theatron f. theaomai behold ]