Last name Нагорниак (Нагорниак 
, Nagorniak 
, Nagornyak 
) , in all the world, is a rare cognomen. The surname Нагорниак is habitual in Czechia, where it is a rare surname, Greece, and Israel, where it is a very rare surname. Measured by absolute frequency, it is commonest in Russia, the United States, and Germany.