discourse vs confab

discourse and confab both are nouns.

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

As verbs, confab is a hyponym of discourse; that is, confab is a word with a more specific, narrower meaning than discourse:

discourse (noun)	confab (noun)
an extended communication (often interactive) dealing with some particular topic	an informal conversation
extended verbal expression in speech or writing
an address of a religious nature (usually delivered during a church service)

discourse (verb)	confab (verb)
talk at length and formally about a topic	talk socially without exchanging too much information
carry on a conversation	have a conference in order to talk something over
to consider or examine in speech or writing