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.Klaas at the Meertens Institute's database of Dutch given names 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.

People with the given name Klaas (fl. 1780), Khoikhoi guide and namesake of Klaas's cuckoo Klaas Afrikaner (fl. 1760–1800), Nama captain of the Orlam Afrikaners Klaas Annink (1710–1775), Dutch serial killer Klaas Bakker (1926–2016), Dutch footballer Klaas Balk (born 1948), Dutch cyclist Klaas van Berkel (born 1953), Dutch historian of science Klaas de Boer (born 1942), Dutch-born American soccer player Klaas Bolt (1927–1990), Dutch organist and improviser Klaas Bom (1937–2025), Dutch engineer Klaas Breeuwer (1901–1961), Dutch footballer Klaas van den Broek (born 1955), Dutch ice hockey player Klaas Bruinsma (1931–2018), Dutch translator to West Frisian Klaas Bruinsma (1953–1991), Dutch drug baron Klaas Buchly (1910–1965), Dutch cyclist Klaas Carel Faber (1922–2012), Dutch WWII war criminal Klaas Dijkhoff (born 1981), Dutch politician and legal scholar Klaas Gerling (born 1981), German DJ known as "Klaas" Klaas de Groot (born 1940), Dutch bioengineer Klaas Gubbels (born 1934), Dutch painter and sculptor Klaas Hendrikse (1947–2018), Dutch atheist pastor Klaas Heufer-Umlauf (born 1983), German television host Klaas van der Horst (1731–1825), Dutch Mennonite teacher and minister Klaas-Jan Huntelaar (born 1983), Dutch footballer Klaas Knot (born 1967), Dutch economist and central banker Klaas Kruik (1678–1754), Dutch cartographer and meteorologist better known as Cruquius Klaas Lodewyck (born 1988), Belgian cyclist Klaas van der Meulen (1642–1693), Dutch glass painter (1930–2008), Dutch organist, pianist, and conductor (1899–1986), Dutch racing cyclist Klaas-Jan van Noortwijk (born 1970), Dutch cricketer Klaas Nuninga (born 1940), Dutch footballer Klaas Ooms (1917–1970), Dutch footballer Klaas Jan Pen (1874–1932), Dutch sports shooter Klaas Plantinga (1846–1922), Dutch distiller Klaas Reimer (1770–1837), Prussian mennonite Klaas Runia (1926–2006), Dutch theologian and journalist Klaas Rusticus (born 1942), Dutch author and television and film director Klaas Schilder (1890–1952), Dutch theologian and professor Klaas Sijtsma, Dutch psychologist Klaas Smit (1930–2008), Dutch footballer Klaas Sybrandi (1807–1872), Dutch Mennonite minister Klaas Sys (born 1986), Belgian cyclists Klaas Twisk (1930–1999), Dutch racing driver Klaas Vantornout (born 1982), Belgian cyclist Klaas Veenhof (1935–2023), Dutch Assyriologist Klaas Veering (born 1981), Dutch field hockey goalkeeper Klaas Vermeulen (born 1988), Dutch field hockey player Klaas de Vries (disambiguation), multiple people Klaas de Waard, alias of Aart Alblas (1918–1944), Dutch navy officer and resistance member (1917–1993), Dutch legal scholar and politician Klaas Woldendorp (1871–1936), Dutch sports shooter Klaas Worp (born 1943), Dutch papyrologist Klaas-Erik Zwering (born 1981), Dutch swimmer and an Olympic medalist

Claas Claas Epp, Jr. (1838–1913), Russian Mennonite minister Claas Hugo Humbert (1830–1904), German scientist and writer

Fiction Klaas Vaak is the traditional Dutch name for the Sandman

People with the surname C. J. Klaas (born 1983), American soccer defensive midfielder Kathrin Klaas (born 1984), German hammer thrower Masabata Klaas (born 1991), South African cricketer Polly Klaas (1981–1993), American murder victim Urmas Klaas (born 1971), is Estonian politician Werner Klaas (1914–1945), German footballer

See also Claus / Klaus, German forms of Klaas Nicholas Klaas's cuckoo (Chrysococcyx klaas), named after Klaas, a Khoikhoi man who found the type specimen Klaas Smits River in Eastern Cape, South Africa

References

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