noun 1 - Dipper is a term used for a female assistant who helped sea swimmers get undressed and prepared for swimming along the shoreline in the 18th century.
noun 2 - A dipper is an individual who walks or jumps into open bodies of water for short durations for fun, relaxation, or a challenge.
To ensure proper modesty, special "bathing machines" were introduced. The "bathing machine" was a small, wooden hut on wheels. Seaside visitors who intended to bathe in the sea could climb into the hut, remove their clothes and change into their swimming costumes without being spied upon. The wheeled huts or "bathing machines" were then rolled or pulled into the sea by strong bathing attendants.
Bathing machine proprietors employed fishermen and their wives to help the swimmer enter into the sea. Tough, muscular fishermen and boatmen assisted the male swimmers and the fishermen's wives, sisters and daughters, if they were strong and sturdy enough for the job, helped to "dip" women and children. The male bathing attendants were generally known as "bathers" and the female attendants, who assisted women and children, were called "dippers".