Surname ألدر (Alder 
, ألدر 
) , globally, is a common cognomen. The cognomen ألدر is characteristic of Switzerland, where it is quite a common surname, Israel, and Paraguay, where it is quite a rare surname. In absolute terms, it most frequently occurs in the United States, the United Kingdom, and Switzerland. Also, ألدر is the forename as well as the last name.