future vs forthcoming

future is a noun but forthcoming is not a noun.

Word	Noun	Adjective	Verb	Adverb
future	Yes	Yes	No	No
forthcoming	No	Yes	No	No

future (noun)	forthcoming (noun)
bulk commodities bought or sold at an agreed price for delivery at a specified future date
a verb tense that expresses actions or states in the future
the time yet to come

future (adjective)	forthcoming (adjective)
yet to be or coming	available when required or as promised
a verb tense or other formation referring to events or states that have not yet happened	of the relatively near future
(of elected officers) elected but not yet serving	at ease in talking to others
effective in or looking toward the future