BT Tam 26b(21) :גזרתא דמצטוותא דסלקי בהו למצטוותא‏ : bench slabs upon which one ascends to the bench
See the entire entry for gzī/ērā, gzīrtā n.f. something cut off: decree, island, circumcision

BT Tam 26b(21) :גזרתא דמצטוותא דסלקי בהו למצטוותא‏ : stone slabs of the bench on which they go up to the bench
See the entire entry for maṣṭəḇā, maṣṭaḇṯā n.f. table, bench