, literally the water trade, is the euphemism for jobs that do not provide a contractually fixed salary, but instead, rely on the popularity of the performer among their fans or clientele. Broadly, it includes the television, theater, and movie industries, but more narrowly, it can refer to those who work in businesses that serve alcohol or sex work. Bars, cabarets, health, hostess bars, image clubs, pink salons and soaplands are all part of the ; though they are not sex workers, geisha and kabuki actors are traditionally considered part of the as well.[1]
While the actual origin of the term  [2] is debatable, it is likely the term came into use during the Tokugawa shogunate (1603–1868).[3] The Tokugawa period saw the development of large bathhouses and an expansive network of roadside inns offering "hot baths and sexual release",[3] as well as the expansion of geisha districts and courtesan quarters in cities and towns throughout the country. Bearing relation to the pleasure-seeking aspects of the, with its antithetical homophone, is a metaphor for floating, drinking, and the impermanence of life, akin to the Western expression "Let us eat and drink, for tomorrow we die" (Isaiah 22:13).[4] [5]
According to one theory proposed by the,[6] the term comes from the Japanese expression, where the literal meaning of the phrase "matter of chance",, is "a matter of water". In the entertainment business, income depends on a large number of fickle factors like popularity among customers, the weather, and the state of the economy; success and failure change as rapidly as the flow of water. The,[7] on the other hand, notes that the term may derive from the expression, for earning a living in the red-light districts, or from the Edo-period expression for a public teahouse.