war vs combat

war and combat both are nouns.

Word	Noun	Adjective	Verb	Adverb
war	Yes	No	Yes	No
combat	Yes	No	Yes	No

war (noun)	combat (noun)
the waging of armed conflict against an enemy	an engagement fought between two military forces
a concerted campaign to end something that is injurious	the act of fighting; any contest or struggle
an active struggle between competing entities
a legal state created by a declaration of war and ended by official declaration during which the international rules of war apply

war (verb)	combat (verb)
make or wage war	battle or contend against in or as if in a battle