for or during the night

to stay overnight.

on or during the previous evening

Preparations were made overnight.

very quickly; suddenly

New suburbs sprang up overnight.

done, made, occurring, or continuing during the night

an overnight stop; an overnight decision.

staying for one night

a group of overnight guests.

designed to be used on a trip or for a journey lasting one night or only a few nights.

intended for delivery on the next day

overnight letters; an overnight package.

valid for one night

The corporal got an overnight pass.

occurring suddenly or within a very short time

a comedian who became an overnight sensation.

Informal . an overnight stay or trip

Our daughter had an overnight at a friend's house.

Informal . a permit for overnight absence, as from a college dormitory

She had an overnight the night of the prom.

the previous evening.

to have an overnight stay or trip

We'll overnight in Denver, then fly on to San Diego.