chemical warfare vs warfare

chemical warfare and warfare both are nouns.

Word	Noun	Adjective	Verb	Adverb
chemical warfare	Yes	No	No	No
warfare	Yes	No	No	No

As nouns, warfare is a hypernym of chemical warfare; that is, warfare is a word with a broader meaning than chemical warfare:

chemical warfare: warfare using chemical agents to kill or injure or incapacitate the enemy
warfare: the waging of armed conflict against an enemy

Other hypernyms of chemical warfare include war.

chemical warfare (noun)	warfare (noun)
warfare using chemical agents to kill or injure or incapacitate the enemy	the waging of armed conflict against an enemy
	an active struggle between competing entities