afterwards vs later

afterwards is not an adjective while later is an adjective.

Word	Noun	Adjective	Verb	Adverb
afterwards	No	No	No	Yes
later	No	Yes	No	Yes

As adverbs, afterwards and later are synonyms defined as:

afterwards and later: happening at a time subsequent to a reference time

Other synonyms of afterwards include after, afterward, later on, subsequently.

afterwards (adjective)	later (adjective)
	at or toward an end or late period or stage of development
	coming at a subsequent time or stage

afterwards (adverb)	later (adverb)
happening at a time subsequent to a reference time	happening at a time subsequent to a reference time
	at some eventual time in the future
	comparative of the adverb `late'