A fungus (Claviceps purpurea) that infects various cereal plants and forms compact black masses of branching filaments that replace many of the grains of the host plant.
The disease caused by such a fungus.
The dried sclerotia of ergot, usually obtained from rye seed and used as a source of several medicinally important alkaloids and as the basic source of lysergic acid.
[French, from Old French argot, cock's spur (from its shape).] er·got'ic adj.
(ûr'gət, -gŏt') 