substantive vs meaningful

substantive is a noun but meaningful is not a noun.

Word	Noun	Adjective	Verb	Adverb
substantive	Yes	Yes	No	No
meaningful	No	Yes	No	No

substantive (noun)	meaningful (noun)
any word or group of words functioning as a noun

substantive (adjective)	meaningful (adjective)
defining rights and duties as opposed to giving the rules by which rights and duties are established	having a meaning or purpose
of or relating to the real nature or essential elements of something
being on topic and prompting thought