Penis — euphemism obtained by modifying the initial letter.
Устарел язык Эзопа,
Стал прозрачен как струя,
Отовсюду светит зопа,
И не скроешь ни фуя.
Aesop’s language is outdated,
Clear as a streaming light,
From everywhere shines the backside,
And nothing stays out of sight.
(И. Губерман)
