Cognomen 西克 (Sieg 
, 西克 
, Sieck ) , in all the world, is quite a common family name. The cognomen 西克 is characteristic of Germany, where it is quite a rare surname, Luxembourg, and Denmark. In absolute terms, it most frequently occurs in Germany, the United States, and Brazil. Much less frequently, 西克 is the forename as well as the last name.