What is "dunk tank"

n. 1 a large tank of water, over which a dunk seat is suspended, which seat can be made to tip or fall into the tank of water, thus dunking whoever is sitting on the seat. It is used as an attraction mainly used in funfairs. 2 any open-topped tank used for dunking.

A dunk tank, also known as a dunking booth or dunking machine, is an attraction mainly used in funfairs, fundraisers, and personal parties. A dunk tank consists of a large tank of water, over which a volunteer is suspended while sitting on a collapsing seat. The game is played by a ball being thrown at a target attached to the tank which, if hit, causes the seat to collapse, "dunking" the person into the tank.