substantive vs meaty

substantive is a noun but meaty is not a noun.

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

As adjectives, substantive and meaty are synonyms defined as:

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

substantive (adjective)	meaty (adjective)
defining rights and duties as opposed to giving the rules by which rights and duties are established	like or containing meat
of or relating to the real nature or essential elements of something	being on topic and prompting thought
being on topic and prompting thought