ウォシュレットWashlet

Washlet (ウォシュレット, Woshuretto) is a registered trademark of the Japanese toilet company Toto, referring to electric toilet seats with water spray feature for washing. While it is commonplace at toilets in Japan, the term washlet may be used colloquially to refer to non-Toto seats with comparable features. The washing feature includes anal and genital cleansing. The buttons associated with operating these features are labeled "oshiri" (bottom) and "bidet". Some models have a sensor that prevents spraying water when a person is not sitting on the toilet. In order to determine the appropriate spray position, Toto surveyed 300 male and female employees during development.

from Washlet (Wikipedia) CC BY SA 3.0