postage stamp vs postage

postage stamp and postage both are nouns.

Word	Noun	Adjective	Verb	Adverb
postage stamp	Yes	No	No	No
postage	Yes	No	No	No

As nouns, postage stamp and postage are synonyms defined as:

postage stamp and postage: a small adhesive token stuck on a letter or package to indicate that postal fees have been paid

Other synonyms of postage stamp include stamp.

postage stamp (noun)	postage (noun)
a small adhesive token stuck on a letter or package to indicate that postal fees have been paid	a small adhesive token stuck on a letter or package to indicate that postal fees have been paid
	the charge for mailing something