expound vs instance

expound is not a noun while instance is a noun.

Word	Noun	Adjective	Verb	Adverb
expound	No	No	Yes	No
instance	Yes	No	Yes	No

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

expound: add details, as to an account or idea; clarify the meaning of and discourse in a learned way, usually in writing
instance: clarify by giving an example of

expound (noun)	instance (noun)
	an item of information that is typical of a class or group
	an occurrence of something

expound (verb)	instance (verb)
add details, as to an account or idea; clarify the meaning of and discourse in a learned way, usually in writing	clarify by giving an example of
state