forenoon vs morning

forenoon and morning both are nouns.

Word	Noun	Adjective	Verb	Adverb
forenoon	Yes	No	No	No
morning	Yes	No	No	No

As nouns, forenoon and morning are synonyms defined as:

Other synonyms of forenoon include morn, morning time.

forenoon (noun)	morning (noun)
the time period between dawn and noon	a conventional expression of greeting or farewell, used to wish someone a good morning
	the earliest period
	the time period between dawn and noon
	the first light of day