Last name Hernaut (Hernaut 
) , all over the world, is a rare cognomen. The family name Hernaut is habitual in Croatia, where it is quite a rare surname, Belgium, where it is a rare surname, and Israel, where it is a very rare surname. Measured by absolute frequency, it most frequently occurs in Croatia, Belgium, and Germany. Very seldom, Hernaut is the forename as well as the last name.