Ranunculus \Ra*nun`cu*lus\, n.; pl. E. {Ranunculuses}, L. {Ranunculi}. [L., a little frog, a medicinal plant, perhaps crowfoot, dim. of rana a frog; cf. raccare to roar.] (Bot.) A genus of herbs, mostly with yellow flowers, including crowfoot, buttercups, and the cultivated ranunculi ({R. Asiaticus}, {R. aconitifolius}, etc.) in which the flowers are double and of various colors.