rankness vs odour

rankness and odour both are nouns.

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

As nouns, odour is a hypernym of rankness; that is, odour is a word with a broader meaning than rankness:

Other hypernyms of rankness include aroma, odor, olfactory property, scent, smell.

rankness (noun)	odour (noun)
the attribute of having a strong offensive smell	any property detected by the olfactory system
the property of producing abundantly and sustaining vigorous and luxuriant growth	the sensation that results when olfactory receptors in the nose are stimulated by particular chemicals in gaseous form