singular vs extraordinary

singular is a noun but extraordinary is not a noun.

Word	Noun	Adjective	Verb	Adverb
singular	Yes	Yes	No	No
extraordinary	No	Yes	No	No

singular (noun)	extraordinary (noun)
the form of a word that is used to denote a singleton

singular (adjective)	extraordinary (adjective)
grammatical number category referring to a single item or unit	beyond what is ordinary or usual; highly unusual or exceptional or remarkable; special
composed of one member, set, or kind	far more than usual or expected
unusual or striking	(of an official) serving an unusual or special function in addition to those of the regular officials
being a single and separate person or thing
the single one of its kind
beyond or deviating from the usual or expected