buttercup vs goldcup

buttercup and goldcup both are nouns.

Word	Noun	Adjective	Verb	Adverb
buttercup	Yes	No	No	No
goldcup	Yes	No	No	No

As nouns, buttercup and goldcup are synonyms defined as:

Other synonyms of buttercup include butter-flower, butterflower, crowfoot, kingcup.

buttercup (noun)	goldcup (noun)
any of various plants of the genus Ranunculus	any of various plants of the genus Ranunculus