odor vs stink

odor and stink both are nouns.

Word	Noun	Adjective	Verb	Adverb
odor	Yes	No	No	No
stink	Yes	No	Yes	No

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

odor: the sensation that results when olfactory receptors in the nose are stimulated by particular chemicals in gaseous form
stink: a distinctive odor that is offensively unpleasant

odor (noun)	stink (noun)
any property detected by the olfactory system	a distinctive odor that is offensively unpleasant
the sensation that results when olfactory receptors in the nose are stimulated by particular chemicals in gaseous form

odor (verb)	stink (verb)
	smell badly and offensively
	be extremely bad in quality or in one's performance