Nightcap
Pronunciation : Night"cap`
Part of Speech : n.
Definition : 1. A cap worn in bed to protect the head, or in undress.
2. A potion of spirit drank at bedtime. [Cant] Wright.
Source : Webster's Unabridged Dictionary, 1913
Merriam-Webster's Everyday Language Reference Set: Includes: The Merriam-Webster Dictionary, The Merriam-Webster Thesaurus, and The Merriam-Webster Vocabulary Builder