art collection vs aggregation

art collection and aggregation both are nouns.

Word	Noun	Adjective	Verb	Adverb
art collection	Yes	No	No	No
aggregation	Yes	No	No	No

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

Other hypernyms of art collection include accumulation, assemblage, collection.

art collection (noun)	aggregation (noun)
a collection of art works	the act of gathering something together
	several things grouped together or considered as a whole