גְּלוֹסְטְרָא, (claustra, clostra, pl.) fastening, lock, bar. Erub. X, 10 נגר שיש בראשו ג׳ a door bolt which has on its top a (movable) fastening contrivance (which may occasionally be used as a pestle). Sabb. 123ᵇ ג׳ (Ar. ק׳, Ms. M. repeatedly גלוסקר׳) the law about claustra, ref. to Kel. XI, 4 ק׳. Sabb. 124ᵃ ג׳.