military post vs fort

military post and fort both are nouns.

Word	Noun	Adjective	Verb	Adverb
military post	Yes	No	No	No
fort	Yes	No	Yes	No

As nouns, fort is a hyponym of military post; that is, fort is a word with a more specific, narrower meaning than military post:

Other hyponyms of military post include garrison, outpost.

military post (noun)	fort (noun)
military installation at which a body of troops is stationed	a fortified defensive structure
	a fortified military post where troops are stationed

military post (verb)	fort (verb)
	station (troops) in a fort
	enclose by or as if by a fortification
	gather in, or as if in, a fort, as for protection or defense