Wank

British vulgar slang for masturbate as performed by males, dates in the spoken language from the late 19th century. Despite the word’s popularity and now widespread use, its origin remains obscure. It is thought to have entered the language when the slang word ‘whang’ was being used for penis. Whang was an earlier dialect word meaning to hit, beat or slap, which are all words associated with male masturbation. Another theory is that wank is a conflation of whack and yank, which again are words associated with male masturbation. In fact, whack off is current American slang for male masturbation.