royal bumps
noun1
Colloquial, Idiomatic A ritual of two or more persons holding another person by the arms and legs, face up, while bumping them repeatedly on the floor. In modern times it is a lighthearted affair, generally performed only on a young person's birthday with the number of bumps corresponding to the person's age in years. Historically it was a hazing.
- I didn't tell the girls it was my birthday. First thing they always did was grab the poor victim's arms and legs and give her the royal bumps.1975, Bess Kaplan, The empty chair, page 43: