clash vs combat

clash and combat both are nouns.

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

As nouns, combat is a hypernym of clash; that is, combat is a word with a broader meaning than clash:

Other hypernyms of clash include fight, fighting, scrap.

clash (noun)	combat (noun)
a minor short-term fight	an engagement fought between two military forces
a loud resonant repeating noise	the act of fighting; any contest or struggle
a state of conflict between persons
a state of conflict between colors

clash (verb)	combat (verb)
disagree violently	battle or contend against in or as if in a battle
crash together with violent impact
be incompatible; be or come into conflict