theater vs combat zone

theater and combat zone both are nouns.

Word	Noun	Adjective	Verb	Adverb
theater	Yes	No	No	No
combat zone	Yes	No	No	No

theater (noun)	combat zone (noun)
a building where theatrical performances or motion-picture shows can be presented	a military area where combat forces operate
the art of writing and producing plays	a city district known for its vice and high crime rate
a region in which active military operations are in progress