'sleepover' originates from the combination of 'sleep' and 'over,' where 'sleep' meant 'to rest' and 'over' indicated 'a period of time.'

'sleepover' evolved from the concept of 'sleeping over' at someone's place, eventually becoming a noun to describe the event.

Initially, it meant 'to sleep at someone else's place,' but over time it evolved into its current meaning of 'a social event involving staying overnight.'