tub stopper vs sink plug

tub stopper and sink plug both are nouns.

Word	Noun	Adjective	Verb	Adverb
tub stopper	Yes	No	No	No
sink plug	Yes	No	No	No

As nouns, tub stopper and sink plug are synonyms defined as:

tub stopper and sink plug: A plug intended for washbasins, bath tubs and other similar water containers.

Other synonyms of tub stopper include basin plug, bath plug.

tub stopper (noun)	sink plug (noun)
A plug intended for washbasins, bath tubs and other similar water containers.	A plug intended for washbasins, bath tubs and other similar water containers.