unpleasant-smelling vs malodourous

unpleasant-smelling and malodourous both are adjectives.

Word	Noun	Adjective	Verb	Adverb
unpleasant-smelling	No	Yes	No	No
malodourous	No	Yes	No	No

As adjectives, unpleasant-smelling and malodourous are synonyms defined as:

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

unpleasant-smelling (adjective)	malodourous (adjective)
having an unpleasant smell	having an unpleasant smell