substantial vs essential

substantial is not a noun while essential is a noun.

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

substantial (noun)	essential (noun)
	anything indispensable

substantial (adjective)	essential (adjective)
having substance or capable of being treated as fact; not imaginary	basic and fundamental
of considerable importance, size, or worth	defining rights and duties as opposed to giving the rules by which rights and duties are established
of or relating to the real nature or essential elements of something	being or relating to or containing the essence of a plant etc
having an abundant supply of money or possessions of value	of the greatest importance
of good quality and condition; solidly built	absolutely necessary; vitally necessary
providing abundant nourishment