odour vs odorous

odour is a noun but odorous is not a noun.

Word	Noun	Adjective	Verb	Adverb
odour	Yes	No	No	No
odorous	No	Yes	No	No

odour (noun)	odorous (noun)
any property detected by the olfactory system
the sensation that results when olfactory receptors in the nose are stimulated by particular chemicals in gaseous form

odour (adjective)	odorous (adjective)
	having odor or a characteristic odor
	having a natural fragrance
	emitting an odor