santonin, n. [L. herba santonica, a kind of plant, fr. Santoni a people of Aquitania; cf. Gr. : cf. F. santonine.].
A white crystalline substance having a bitter taste, extracted from the buds of levant wormseed and used as an anthelmintic. It occassions a peculiar temporary color blindness, causing objects to appear as if seen through a yellow glass. [1913 Webster]