essentially vs essential

essentially is not a noun while essential is a noun.

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

essentially (noun)	essential (noun)
	anything indispensable

essentially (adjective)	essential (adjective)
	basic and fundamental
	defining rights and duties as opposed to giving the rules by which rights and duties are established
	being or relating to or containing the essence of a plant etc
	of the greatest importance
	absolutely necessary; vitally necessary

essentially (adverb)	essential (adverb)
in essence; at bottom or by one's (or its) very nature