From king + cup
kingcup (plural kingcups)
- (Britain, regional) Any of various species of buttercup, or the marsh marigold, Caltha palustris.
- 1979, Angela Carter, ‘The Erl-King’, The Bloody Chamber, Vintage 2006, p. 99:
- He told me how the wise toad who squats among the kingcups by the stream in summer has a very precious jewel in his head.