aggression vs armed combat

aggression and armed combat both are nouns.

Word	Noun	Adjective	Verb	Adverb
aggression	Yes	No	No	No
armed combat	Yes	No	No	No

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

Other hypernyms of aggression include combat.

aggression (noun)	armed combat (noun)
violent action that is hostile and usually unprovoked	an engagement fought between two military forces
deliberately unfriendly behavior
the act of initiating hostilities
a disposition to behave aggressively
a feeling of hostility that arouses thoughts of attack