TgO Gen21:19 :וַחזָת בֵירָא דְמַיָא וַאֲזַלַת וֻמלָת יָת רוּקבָא מַיָא‏ : she saw a water cistern so she went and filled the skin with water
See the entire entry for *rqeḇ, raqbā n.m. water-skin