Motherfucker, tosser, arsehole. Derived from a combination of the vulgar roots мудо (testicles) and ебать (to fuck). In strong Russian slang, it is a highly offensive compound insult used to describe a deeply stupid, annoying, contemptible, or utterly incompetent man whose behavior causes severe irritation.
Антон Лысенко: Какая машина вообще не ломается?
Владислав Сергеевич: Любая ломается, если водитель мудоёб (уж простите).
Anton Lysenko: What car doesn’t break down at all?
Vladislav Sergeyevich: Every car will break down if the driver is a wanker (excuse my French).
(google.ru, 09/2011)
