theatre vs theater

theatre and theater both are nouns.

Word	Noun	Adjective	Verb	Adverb
theatre	Yes	No	No	No
theater	Yes	No	No	No

As nouns, theatre and theater are synonyms defined as:

theatre and theater: a building where theatrical performances or motion-picture shows can be presented

Other synonyms of theatre include house.

As nouns, theatre and theater are synonyms defined as:

Other synonyms of theatre include dramatic art, dramatics, dramaturgy.

As nouns, theatre and theater are synonyms defined as:

theatre and theater: a region in which active military operations are in progress

Other synonyms of theatre include field, field of operations, theater of operations, theatre of operations.

theatre (noun)	theater (noun)
a building where theatrical performances or motion-picture shows can be presented	a building where theatrical performances or motion-picture shows can be presented
the art of writing and producing plays	the art of writing and producing plays
a region in which active military operations are in progress	a region in which active military operations are in progress