have an early/a late night

have a late night

To go to sleep later than one typically does. She must have had a late night last night considering how she yawned all through that meeting.
See also: have, late, night

have an early night

To go to sleep earlier than one typically does. You need to have an early night tonight so that you're well-rested for your exam tomorrow.
See also: early, have, night

have an early/a late ˈnight

go to bed earlier or later than usual: I’d better have an early night if I want to get up at 6 o’clock.I’ve had a lot of late nights recently.
See also: early, have, late, night