(idiomatic) Middle of the night.

Lasting a night (i.e. the duration of one night); lasting all night.

Through the night.

(UK) Alternative form of all cats are grey in the dark

(US) Alternative form of all cats are grey in the dark

A warm cloth cap worn while sleeping, often with pajamas, being common attire in northern Europe before effective home heating became widespread. / A beverage drunk before bed that is usually alcoholic.

(intransitive) To drink an alcoholic beverage shortly before retiring to bed.

Alternative spelling of Saturday-night special

Something stealthy or that occurs without warning.

(archaic) comparative form of nigh: more nigh