agglomeration vs accumulation

agglomeration and accumulation both are nouns.

Word	Noun	Adjective	Verb	Adverb
agglomeration	Yes	No	No	No
accumulation	Yes	No	No	No

As nouns, accumulation is a hypernym of agglomeration; that is, accumulation is a word with a broader meaning than agglomeration:

Other hypernyms of agglomeration include aggregation, assemblage, collection.

agglomeration (noun)	accumulation (noun)
the act of collecting in a mass; the act of agglomerating	the act of accumulating
a jumbled collection or mass	several things grouped together or considered as a whole
	(finance) profits that are not paid out as dividends but are added to the capital base of the corporation
	an increase by natural growth or addition