cost vs postulate

cost and postulate both are nouns.

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

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

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

cost (noun)	postulate (noun)
the property of having material worth (often indicated by the amount of money something would bring if sold)	(logic) a proposition that is accepted as true in order to provide a basis for logical reasoning
value measured by what must be given or done or undergone to obtain something
the total spent for goods or services including money and time and labor

cost (verb)	postulate (verb)
be priced at	take as a given; assume as a postulate or axiom
require to lose, suffer, or sacrifice	maintain or assert
	require as useful, just, or proper