confab vs discuss

confab is a noun but discuss is not a noun.

Word	Noun	Adjective	Verb	Adverb
confab	Yes	No	Yes	No
discuss	No	No	Yes	No

As verbs, discuss is a hypernym of confab; that is, discuss is a word with a broader meaning than confab:

confab: have a conference in order to talk something over
discuss: speak with others about (something); talk (something) over in detail; have a discussion

Other hypernyms of confab include hash out, talk over.

confab (noun)	discuss (noun)
an informal conversation

confab (verb)	discuss (verb)
talk socially without exchanging too much information	speak with others about (something); talk (something) over in detail; have a discussion
have a conference in order to talk something over	to consider or examine in speech or writing