clepsydra (noun F) : κλεψύδρα
* An instrument for measuring time by water, similar to our sand-glasses, a water-clock, clepsydra, Sen. Ep. 24, 19; Veg. Mil. 3, 8; App. M. 3, p. 130, 19; used by speakers to measure the length of their discourse,Cic. Tusc. 2, 27, 67; Plin. Ep. 2, 11, 14; 6, 2, 5; 1, 23, 2.—Meton., the time measured by the clepsydra, and hence, petere clepsydram, to ask leave to speak; and dare clepsydram, to give leave to speak, Cic. de Or. 3, 34, 138; Mart. 6, 35; cf. aqua, II. F., and Dict. of Antiq. pp. 508 sq.

s. TLL