odorous vs odour

odorous is not a noun while odour is a noun.

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

odorous (noun)	odour (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

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