It's often used in terms like:
* Epilepsy: A neurological disorder characterized by recurrent seizures.
* Narcolepsy: A neurological disorder characterized by excessive daytime sleepiness.
* Cataplexy: A sudden loss of muscle tone often triggered by strong emotions.
Note: While "-lepsy" means "slipping", it doesn't always refer to physical slipping. In the context of neurological disorders, it often refers to a sudden loss of control or function, like slipping into unconsciousness or muscle weakness.