Surname Bitr (Bitter 
, Bitur 
, Bitr 
) , around the world, is a common last name. The cognomen Bitr is characteristic of Antigua and Barbuda, where it is quite a common surname, Germany, where it is quite a rare surname, and Hungary. Measured by absolute frequency, this name is the most popular in Germany, the United States, and India. Very seldom, Bitr is the forename as well as the last name.