kingcup vs butter-flower

kingcup and butter-flower both are nouns.

Word	Noun	Adjective	Verb	Adverb
kingcup	Yes	No	No	No
butter-flower	Yes	No	No	No

As nouns, kingcup and butter-flower are synonyms defined as:

kingcup and butter-flower: any of various plants of the genus Ranunculus

Other synonyms of kingcup include buttercup, butterflower, crowfoot, goldcup.

kingcup (noun)	butter-flower (noun)
any of various plants of the genus Ranunculus	any of various plants of the genus Ranunculus
swamp plant of Europe and North America having bright yellow flowers resembling buttercups