adjective vs procedural

adjective is a noun but procedural is not a noun.

Word	Noun	Adjective	Verb	Adverb
adjective	Yes	Yes	No	No
procedural	No	Yes	No	No

As adjectives, adjective and procedural are synonyms defined as:

adjective and procedural: relating to court practice and procedure as opposed to the principles of law

adjective (noun)	procedural (noun)
a word that expresses an attribute of something
the word class that qualifies nouns

adjective (adjective)	procedural (adjective)
relating to court practice and procedure as opposed to the principles of law	relating to court practice and procedure as opposed to the principles of law
of or relating to or functioning as an adjective	of or relating to procedure