シアターは英語で
theater

英語の定義

theater
1. n. A 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. n. A 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. n. A lecture theatre.
4. n. (medicine) An operating theatre or locale for human experimentation.
This man is about to die, get him into theater at once!
5. n. (US) A cinema.
We sat in the back row of the theater and threw popcorn at the screen.
6. n. Drama or performance as a profession or artform.
I worked in the theater for twenty-five years.