individual vs several

individual is a noun but several is not a noun.

Word	Noun	Adjective	Verb	Adverb
individual	Yes	Yes	No	No
several	No	Yes	No	No

individual (noun)	several (noun)
a human being; person, singular, assertive existential pronoun; pronoun, person, singular; quantifier: assertive existential
a single organism

individual (adjective)	several (adjective)
being or characteristic of a single thing or person	distinct and individual
separate and distinct from others of the same kind	considered individually
concerning one person exclusively	(used with count nouns) of an indefinite number more than 2 or 3 but not many
characteristic of or meant for a single person or thing