Definitions
1.nounA place or building, consisting of a stage and seating, in which an audience gathers to watch plays, musical performances, public ceremonies, and so on.
2.nounA region where a particular action takes place; a specific field of action, usually with reference to war."His grandfather was in the Pacific theater during the war."
3.nounA lecture theatre.
4.nounAn operating theatre or locale for human experimentation."This man is about to die, get him into theater at once!"
5.nounA cinema."We sat in the back row of the theater and threw popcorn at the screen."
6.nounDrama or performance as a profession or art form."I worked in theater for twenty-five years."
7.nounAny place rising by steps like the seats of a theater.