1) Given name 
Diderik (also Diederik, Dederik) is a male given name, the Low German and Low Franconian form of High German Dietrich. In North Germanic languages, the native form would be Tjodrik, but Diderik has been loaned from Low German and is now a common name also in Scandinaiva. See Theodoric for the origin and history of the name. Common short forms of t...