Augean stables vs plural

Augean stables and plural both are nouns.

Word	Noun	Adjective	Verb	Adverb
Augean stables	Yes	No	No	No
plural	Yes	Yes	No	No

Augean stables (noun)	plural (noun)
(Greek mythology) the extremely dirty stables that were finally cleaned by Hercules who diverted two rivers through them	the form of a word that is used to denote more than one

Augean stables (adjective)	plural (adjective)
	grammatical number category referring to two or more items or units
	composed of more than one member, set, or kind