odour vs fragrance

odour and fragrance both are nouns.

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

As nouns, fragrance is a hyponym of odour; that is, fragrance is a word with a more specific, narrower meaning than odour:

As nouns, fragrance is a hyponym of odour; that is, fragrance is a word with a more specific, narrower meaning than odour:

odour: the sensation that results when olfactory receptors in the nose are stimulated by particular chemicals in gaseous form
fragrance: a distinctive odor that is pleasant

Other hyponyms of odour include scent, aroma, perfume, scent, fetor, foetor, malodor, malodour, mephitis, reek, stench, stink, acridity, stank.

odour (noun)	fragrance (noun)
any property detected by the olfactory system	a pleasingly sweet olfactory property
the sensation that results when olfactory receptors in the nose are stimulated by particular chemicals in gaseous form	a distinctive odor that is pleasant