[the.ater] or the.atre n [ME theatre, fr. MF, fr. L theatrum, fr. Gk theatron, fr. theasthai to view, fr. thea act of seeing; akin to Gk thauma miracle] (14c) 1 a: an outdoor structure for dramatic performances or spectacles in ancient Greece and Rome b: a building for dramatic performances c: a building or area for showing motion pictures
2: a place or sphere of enactment of usu. significant events or action "the ~ of public life" 3 a: a place rising by steps or gradations "a woody ~ of stateliest view --John Milton" b: a room often with rising tiers of seats for assemblies (as for lectures or surgical demonstrations)
4. a: dramatic literature: plays b: dramatic representation as an art or profession: drama
5. a: dramatic or theatrical quality or effectiveness b: spectacle 1a
[2]theater adj (1977): of, relating to, or appropriate for use in a theater of operations "~ nuclear weapons"