rough-and-tumble vs combat

rough-and-tumble and combat both are nouns.

Word	Noun	Adjective	Verb	Adverb
rough-and-tumble	Yes	Yes	No	No
combat	Yes	No	Yes	No

As nouns, combat is a hypernym of rough-and-tumble; that is, combat is a word with a broader meaning than rough-and-tumble:

Other hypernyms of rough-and-tumble include fight, fighting, scrap.

rough-and-tumble (noun)	combat (noun)
disorderly fighting	an engagement fought between two military forces
	the act of fighting; any contest or struggle

rough-and-tumble (adjective)	combat (adjective)
characterized by disorderly action and disregard for rules

rough-and-tumble (verb)	combat (verb)
	battle or contend against in or as if in a battle