Definitions from Wiktionary ( )

▸ noun:  (clothing) A warm cloth cap worn while sleeping, often with pajamas, being common attire in northern Europe before effective home heating became widespread.
▸ noun:  A beverage drunk before bed that is usually alcoholic.
▸ noun:  (by extension, figuratively) Something that a person reads or listens to before bed.
▸ noun:  (US, sports, baseball) The final match of a sporting contest, especially the second game of a baseball doubleheader.
▸ noun:  (historical) A cap drawn over the face of the condemned person before they are hanged.
▸ verb:  (intransitive) To drink an alcoholic beverage shortly before retiring to bed.

---

▸ Word origin

▸ Words similar to nightcap
▸ Usage examples for nightcap

▸ Idioms related to nightcap
▸ Wikipedia articles (New!)
▸ Popular adjectives describing nightcap
▸ Words that often appear near nightcap
▸ Rhymes of nightcap

▸ Invented words related to nightcap