infighting vs combat

infighting and combat both are nouns.

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

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

infighting: conflict between members of the same organization (usually concealed from outsiders)
combat: the act of fighting; any contest or struggle

Other hypernyms of infighting include fight, fighting, scrap.

infighting (noun)	combat (noun)
boxing at close quarters	an engagement fought between two military forces
conflict between members of the same organization (usually concealed from outsiders)	the act of fighting; any contest or struggle

infighting (verb)	combat (verb)
	battle or contend against in or as if in a battle