The definition of a nightcap is a cap worn to bed at night to keep the head warm.(noun)
An example of a nightcap is a beanie placed on a newborn baby's head while sleeping.
Nightcap is defined as an alcoholic drink at the end of the night.(noun)
An example of a nightcap is two friends having a glass of grappa after a night out.
See nightcap in Webster's New World College Dictionary
See nightcap in American Heritage Dictionary 4
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