contents vs aggregation

contents and aggregation both are nouns.

Word	Noun	Adjective	Verb	Adverb
contents	Yes	No	No	No
aggregation	Yes	No	No	No

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

contents: (usually plural) everything that is included in a collection and that is held or included in something
aggregation: several things grouped together or considered as a whole

Other hypernyms of contents include accumulation, assemblage, collection.

contents (noun)	aggregation (noun)
a list of divisions (chapters or articles) and the pages on which they start	the act of gathering something together
(usually plural) everything that is included in a collection and that is held or included in something	several things grouped together or considered as a whole