a black or dark purple club-shaped sclerotium (hard mass of fungal threads) that develops in place of the seed of a grass, e.g. rye
a fungus bearing such sclerotia: genus Claviceps
a disease of rye and other cereals caused by a fungus that produces a mass of dark threads in the ear of the plant an ergot fungus
the dried sclerotia of an ergot fungus containing ergotamine and other alkaloids, used medicinally
ergotic /uhʹgotik/ adj
[French ergot, literally ‘cock's spur’; because grain affected by ergot resembles a claw]