discussion vs detail

discussion and detail both are nouns.

Word	Noun	Adjective	Verb	Adverb
discussion	Yes	No	No	No
detail	Yes	No	Yes	No

As nouns, detail is a hyponym of discussion; that is, detail is a word with a more specific, narrower meaning than discussion:

discussion: an extended communication (often interactive) dealing with some particular topic
detail: extended treatment of particulars

Other hyponyms of discussion include dilation, consideration, talk, elaboration, enlargement, expansion.

discussion (noun)	detail (noun)
an exchange of views on some topic	an isolated fact that is considered separately from the whole
an extended communication (often interactive) dealing with some particular topic	extended treatment of particulars
	a temporary military unit
	a crew of workers selected for a particular task
	a small part that can be considered separately from the whole

discussion (verb)	detail (verb)
	assign to a specific task
	provide details for