[er.got] n [F, lit., cock's spur] (1683) 1: the black or dark purple sclerotium of fungi (genus Claviceps) that occurs as a club-shaped body replacing the seed of a grass (as rye); also: a fungus bearing ergots
2: a disease of rye and other cereals caused by an ergot fungus 3 a: the dried sclerotia of an ergot fungus grown on rye and containing several alkaloids (as ergonovine and ergotamine) b: any of such alkaloids used medicinally for their contractile effect on smooth muscle (as of peripheral arterioles) -- er.got.ic adj