Klaas is a Dutch male given and surname. It is the Dutch short form of Nicholas (Dutch: Nicolaas), a Greek name ultimately meaning victory of the people. A traditionally common name in the Netherlands, its popularity declined some 20-fold since 1950. Archaic spellings include Claas and Claes. Among its female derivatives are Klaasje, Clasien, Clasina, Clasine, Clazien, Klasien, Klasina and Klaziena. Klaas also exists as a patronymic surname, though the forms Klaasen, Klaassen, Claassen, Claessen, and Claessens are more common.
