govern vs postulate

govern is not a noun while postulate is a noun.

Word	Noun	Adjective	Verb	Adverb
govern	No	No	Yes	No
postulate	Yes	No	Yes	No

As verbs, postulate is a hypernym of govern; that is, postulate is a word with a broader meaning than govern:

Other hypernyms of govern include ask, call for, demand, involve, necessitate, need, require, take.

govern (noun)	postulate (noun)
	(logic) a proposition that is accepted as true in order to provide a basis for logical reasoning

govern (verb)	postulate (verb)
exercise authority over; as of nations	take as a given; assume as a postulate or axiom
direct or strongly influence the behavior of	maintain or assert
bring into conformity with rules or principles or usage; impose regulations	require as useful, just, or proper
require to be in a certain grammatical case, voice, or mood