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

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.

plural of nightcap

Third-person singular simple present indicative form of nightcap

Wearing a nightcap. / (law) (of a warrant) that can be executed any time, as opposed to non-nightcapped, that can only be executed during the daytime on business days

simple past tense and past participle of nightcap

present participle of nightcap