It's commonly used in medical terms to denote a sudden, involuntary attack or seizure, particularly in the context of neurological disorders.
Here are some examples:
* Epilepsy: A neurological disorder characterized by recurrent seizures.
* Narcolepsy: A sleep disorder characterized by excessive daytime sleepiness and sudden attacks of sleep.
* Catalepsy: A state of muscular rigidity and immobility.
Therefore, the suffix "-lepsy" essentially signifies a condition marked by sudden, uncontrollable episodes.