Family name רידל (Riedel 
, Riddle 
, Riedl ) , throughout the world, is a widespread surname. The family name רידל is characteristic of Austria, where it is quite a common surname, Germany, and Eswatini (explore the name in all countries). Measured by absolute frequency, the name is most common in Germany, the United States, and Austria. Much less frequently, רידל is the forename as well as the last name.