A generalized-onset seizure is a type of seizure originating at some point within, and rapidly engaging, bilaterally distributed networks. The networks may include cortical and subcortical structures but not necessarily the entire cortex. The phenotype is Human Phenotype Ontology term HP_0002197 (Generalized-onset seizure). Also known as: Generalised onset seizure, Generalised seizures, Generalised-onset seizure, Generalized onset seizure, Generalized seizures, Generalized-onset seizures, Primary generalised seizure, Primary generalized seizure.