medical specialty vs parenteral

medical specialty is a noun but parenteral is not a noun.

Word	Noun	Adjective	Verb	Adverb
medical specialty	Yes	No	No	No
parenteral	No	Yes	No	No

medical specialty (noun)	parenteral (noun)
the branches of medical science that deal with nonsurgical techniques

medical specialty (adjective)	parenteral (adjective)
	located outside the alimentary tract
	administered by means other than through the alimentary tract (as by intramuscular or intravenous injection)