אֵיסוּר m. (אסר) 1) imprisonment. Ber. 28ᵇ אין אֵיסוּרוֹ א׳ עולם the imprisonment which he decrees is not everlasting (as he may die and his successor may relieve me). 2) * (= אָסִיר), pl. אֵיסוּרִין prisoners. Ex. R. s. 30 he burst the prison open והוציא האיסו׳ (ib. also האֵיסָרִין) and set the prisoners free [prob. to be read אסירין].