stamp collecting vs collection

stamp collecting and collection both are nouns.

Word	Noun	Adjective	Verb	Adverb
stamp collecting	Yes	No	No	No
collection	Yes	No	No	No

As nouns, collection is a hypernym of stamp collecting; that is, collection is a word with a broader meaning than stamp collecting:

Other hypernyms of stamp collecting include aggregation, assembling, collecting.

stamp collecting (noun)	collection (noun)
the collection and study of postage stamps	the act of gathering something together
	a publication containing a variety of works
	request for a sum of money
	several things grouped together or considered as a whole