purpose vs final cause

purpose and final cause both are nouns.

Word	Noun	Adjective	Verb	Adverb
purpose	Yes	No	Yes	No
final cause	Yes	No	No	No

As nouns, final cause is a hyponym of purpose; that is, final cause is a word with a more specific, narrower meaning than purpose:

purpose: an anticipated outcome that is intended or that guides your planned actions
final cause: (philosophy) the end or purpose of a thing or process

Other hyponyms of purpose include idea, mind, cross-purpose, sake, view, will.

purpose (noun)	final cause (noun)
what something is used for	(philosophy) the end or purpose of a thing or process
the quality of being determined to do or achieve something; firmness of purpose
an anticipated outcome that is intended or that guides your planned actions

purpose (verb)	final cause (verb)
reach a decision
propose or intend