קַסְטְלִין m. (castellum, καστέλλιν S.) 1) fort, castle. Y. Ab. Zar. III, 42ᶜ נפל ק׳ דטיבריא (ed. Krot. קסיטולין, corr. acc.) the castle of Tiberias fell in (burying the idol placed therein). —2) reservoir. Tosef. Mikv. IV, 6 ק׳ המחליק מים וכ׳ a reservoir which distributes water (in pipes) in the cities.