Last name Ianush (Януш 
, Ianush 
, Иануш ) , throughout the world, is quite a rare surname. The surname Ianush is characteristic of Ukraine, where it is quite a rare surname, Belarus, and Georgia, where it is a rare surname. Measured by absolute frequency, this name is the most popular in Eastern Europe, particularly Ukraine, Russia, and Belarus. Likewise, Ianush is the forename as well as the last name.