theater 是 theatre 的美式拼法，意思一樣。多益（TOEIC）用美式拼法。
theater · theatre
核心畫面
Picture a space built around one lit centre with everyone facing it: something happens in the middle and people watch. Fill the middle with actors and you have the building and the art form. Keep the layout but change what is in the middle — an operation, a war — and English still reaches for the same word.
可以想成：一個以「中間那塊亮處」為中心蓋起來的空間，所有人的臉都朝著它——事情在中間發生，其他人在旁邊看。中間站的是…更多收起
可以想成：一個以「中間那塊亮處」為中心蓋起來的空間，所有人的臉都朝著它——事情在中間發生，其他人在旁邊看。中間站的是演員，就是劇院和戲劇這門藝術；把格局留著、換掉中間的東西（一場手術、一場戰爭），英文仍然用同一個字。原始詞典資料8 筆記錄
以下是外部詞典記錄的用法，原文照列，我們還沒有寫成教學內容。上面的說明才是我們自己寫的；有些用法可能上面已經講過了。
theaternoun/ˈθi(ə)tɚ/
- 1
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
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.
- Percy had been too big for the town since he got back from the war. He served in the Pacific theater, behind the lines keeping up the supply chain.
- 3
A lecture theatre.
- 4
medicinesciencesAn operating theatre or locale for human experimentation.
- This man is about to die, get him into theater at once!
- 5
A cinema.
- We sat in the back row of the theater and threw popcorn at the screen.
- 6
Drama or performance as a profession or art form.
- I worked in theater for twenty-five years.
- 7
Any place rising by steps like the seats of a theater.
- 8
derogatoryA conspicuous but unproductive display of action.
- The Senate confirmation hearings were just theater.
- security theater; hygiene theater
資料來源：英文維基詞典 English Wiktionary（CC BY-SA 4.0）。 原文照列，未經改寫。