You searched for: “thalassotherapy
thalassotherapy (s) (noun), thalassotherapies (pl)
The treatment of an illness with sea water: Dr. Smith told Joan that a thalassotherapy would help her ailment by bathing in a hot tub of seawater or by applying a sea product, such as seaweed, onto their bodies.

Some people think that an ocean cruise can provide them with thalassotherapies when they use the therapeutic pools of water on board.