armed forces vs theater

armed forces and theater both are nouns.

Word	Noun	Adjective	Verb	Adverb
armed forces	Yes	No	No	No
theater	Yes	No	No	No

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