0 a party when a group of children spend the night at one child's house --
1 a party in which a group of friends, esp. girls, sleep at one friend’s home --
Martin had hung out with her earlier that day before the dance and was to pick her up and take her to a slumber party across town.
Their first performance was at his younger sister's slumber party.
The boys frequently engage in activities which most teenage boys have outgrown, such as slumber parties.
In 2006 the square played host to an all-city pillow fight, and later an all-city slumber party.
We have slumber party sing-a-longs, we make up dance routines in our pajamas.
She (voluntarily) takes a bath and even accepts an invitation to a slumber party.