Surname Rihak (Rihak 
) , around the globe, is a rare cognomen. The last name Rihak is habitual in Czechia, where it is quite a rare surname, Slovakia, and Estonia, where it is a rare surname. Not in comparison with a country's population, this name is the most popular in Czechia, Slovakia, and Germany. Very seldom, Rihak is the forename as well as the last name.