Willy, dicky, pee-pee. A highly common, informal noun derived from the baby-talk verb писять (“to wee,” “to pee”) combined with the expressive noun suffix -ун. In everyday slang and colloquial speech, it functions as a mild, childish term for a penis. It is rarely used aggressively; instead, it is typically employed by parents when talking to young children, or used playfully or slightly dismissively among adults to refer to a small or unimpressive member.
Девочка разговорчивая и приветливая но не такая болтушка, что заткнуть можно только писюном в гланды.
Girl is talkative and affable but not so chatty that you can only shut her up with a weener up to the glands.
(Дон Сигизмунд @ sextalk.ru, 02/2022)
