Family name Onkin (Onkin 
, Онкин 
, Онькин ) , all over the world, is a rare cognomen. The last name Onkin is characteristic of Belarus, where it is a rare surname, Russia, and Kazakhstan, where it is a very rare surname. Measured by absolute frequency, it most frequently occurs in Russia, Belarus, and China. Also, Onkin is the forename as well as the last name.