scent vs odour

scent and odour both are nouns.

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

As nouns, scent and odour are synonyms defined as:

Other synonyms of scent include aroma, odor, olfactory property, smell.

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

scent: an odor left in passing by which a person or animal can be traced
odour: the sensation that results when olfactory receptors in the nose are stimulated by particular chemicals in gaseous form

Other hypernyms of scent include odor, olfactory perception, olfactory sensation, smell.

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

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

Other hypernyms of scent include odor, olfactory perception, olfactory sensation, smell.

scent (noun)	odour (noun)
any property detected by the olfactory system	any property detected by the olfactory system
an odor left in passing by which a person or animal can be traced	the sensation that results when olfactory receptors in the nose are stimulated by particular chemicals in gaseous form
a distinctive odor that is pleasant