It is called "Springer" (translates to: jumper) in German. Sometimes "Pferd" or "Ross" is also used (translates to: horse and steed, resp.). That's why "Knight's tour" is called "Springerproblem" or "Rösselsprung" (from "Ross") in German.
(Not to be confused with the much larger Axel-Springer publishers, nor the American academic Springer publisher.)