nightfall vs gloam

nightfall and gloam both are nouns.

Word	Noun	Adjective	Verb	Adverb
nightfall	Yes	No	No	No
gloam	Yes	No	No	No

As nouns, nightfall and gloam are synonyms defined as:

Other synonyms of nightfall include crepuscle, crepuscule, dusk, evenfall, fall, gloaming, twilight.

nightfall (noun)	gloam (noun)
the time of day immediately following sunset	the time of day immediately following sunset