theoretical vs academic

theoretical is not a noun while academic is a noun.

Word	Noun	Adjective	Verb	Adverb
theoretical	No	Yes	No	No
academic	Yes	Yes	No	No

theoretical (noun)	academic (noun)
	an educator who works at a college or university

theoretical (adjective)	academic (adjective)
concerned primarily with theories or hypotheses rather than practical considerations	associated with academia or an academy
concerned with theories rather than their practical applications	marked by a narrow focus on or display of learning especially its trivial aspects
	hypothetical or theoretical and not expected to produce an immediate or practical result