Family name Sirek (Sirek 
) , all over the world, is quite a rare cognomen. The last name Sirek is characteristic of Eastern Europe, particularly Czechia, where it is quite a rare surname, Slovakia, where it is a rare surname, and Poland. In absolute terms, this name is the most popular in the United States, Czechia, and Poland. Likewise, Sirek is the forename as well as the last name.