To dream of a nightcap represents a situation in your life soothes concerns or makes it easier to forget something. Parting gift, condolences, or reparations.
Numbing your pain or concerns away.
Example: A man dreamed that his father offered him a nightcap. In waking life his father died leaving him with a million dollars in property just as the man was about to go bankrupt. The nightcap symbolized the emotional numbing of the money on his bankruptcy.