A whirlpool bath is a type of SPA treatment that involves a large tub filled with hot water and jets of air or water that create a swirling effect. This type of bath is often used to provide relaxation and relief from muscle tension, as well as to help improve circulation. The term 'whirlpool bath' is derived from the combination of the words 'WHIRL' and 'POOL, ' which refer to the swirling motion of the water.