a generalized seizure characterized by the sudden onset of tonic contraction of the muscles often associated with a cry or moan, and frequently resulting in a fall to the ground. The tonic phase of the seizure gradually give way to clonic convulsive movements occurring bilaterally and synchronously before slowing and eventually stopping, followed by a variable period of unconsciousness and gradual recovery. SYN: cryptogenic epilepsy, generalized tonic-clonic epilepsy, grand mal seizure, grand mal, idiopathic epilepsy (2), major epilepsy.