rich vs substantial

rich is a noun but substantial is not a noun.

Word	Noun	Adjective	Verb	Adverb
rich	Yes	Yes	No	No
substantial	No	Yes	No	No

rich (noun)	substantial (noun)
people who have possessions and wealth (considered as a group)

rich (adjective)	substantial (adjective)
possessing material wealth	having substance or capable of being treated as fact; not imaginary
having an abundant supply of desirable qualities or substances (especially natural resources)	of considerable importance, size, or worth
suggestive of or characterized by great expense	of or relating to the real nature or essential elements of something
high in mineral content; having a high proportion of fuel to air	having an abundant supply of money or possessions of value
causing indignation due to hypocrisy	of good quality and condition; solidly built
affording an abundant supply	providing abundant nourishment
strong; intense
marked by great fruitfulness
pleasantly full and mellow
marked by richness and fullness of flavor
containing plenty of fat, or eggs, or sugar
of great worth or quality
very productive