military vs volunteer

military and volunteer both are nouns.

Word	Noun	Adjective	Verb	Adverb
military	Yes	Yes	No	No
volunteer	Yes	Yes	Yes	No

military (noun)	volunteer (noun)
the military forces of a nation	a person who performs voluntary work
	(military) a person who freely enlists for service

military (adjective)	volunteer (adjective)
associated with or performed by members of the armed services as contrasted with civilians	without payment
characteristic of or associated with soldiers or the military
of or relating to the study of the principles of warfare