malodorous vs stinky

malodorous and stinky both are adjectives.

Word	Noun	Adjective	Verb	Adverb
malodorous	No	Yes	No	No
stinky	No	Yes	No	No

As adjectives, malodorous and stinky are synonyms defined as:

Other synonyms of malodorous include ill-smelling, malodourous, unpleasant-smelling.

malodorous (adjective)	stinky (adjective)
having an unpleasant smell	having an unpleasant smell
	very bad