Surname รู้ธ (Rut 
, รู้ธ) , globally, is a common last name. The surname รู้ธ is characteristic of Israel, where it is a common surname, Iceland, where it is quite a common surname, and Honduras, where it is quite a rare surname. Measured by absolute frequency, this name is the most popular in Israel, Mexico, and Spain. More prevalently, รู้ธ is the forename as well as the last name.