Save Gender Feminine Usage German (Austrian), Upper German Pronounced Pron. /ˈʁeː.zɐl/(Upper German) [key·simplify] Meaning & History Austrian and Bavarian German diminutive of Theresa, Therese and Theresia.It is rarely used as an official given name. One known namesake is the German politician Reserl Sem née Fürstberger (b. 1953).