gab vs chat

gab and chat both are nouns.

Word	Noun	Adjective	Verb	Adverb
gab	Yes	No	Yes	No
chat	Yes	No	Yes	No

As nouns, chat is a hypernym of gab; that is, chat is a word with a broader meaning than gab:

Other hypernyms of gab include confab, confabulation, schmoose, schmooze.

gab (noun)	chat (noun)
light informal conversation for social occasions	songbirds having a chattering call
	birds having a chattering call
	an informal conversation

gab (verb)	chat (verb)
talk profusely	talk socially without exchanging too much information