German masc. name and surname, literally "folk-rule" (Dutch Diederik), from Old High German Theodric, from theuda "folk, people" (see Teutonic) + rihhi "rule" (see Reich). Variants or familiar forms include Derrick, Dierks, Dieter, Dirk. Compare Theodoric. Theodric the Ostrogoth, who held sway in Italy 493-526, appears in later German tales as Dietrich von Bern (Verona).