vas, vadis, m., a bail, security, surety (in gen., while praes is confined to pecuniary matters; cf. also sponsio): vas appellatus, qui pro altero vadimonium promittebat, Varr. L. L. 6, 74 Mull.: vas factus est alter (Damon) ejus sistendi, ut si ille non revertisset, moriendum esset ipsi, Cic. Off. 3, 10, 45: vades poscere, id. Rep. 2, 36, 61: se dare vadem pro amico, id. Fin. 2, 24, 79: deserere vades, Liv. 39, 41, 7; Hor. S. 1, 1, 11 Heind.

— Trop.: vestram virtutem rerum quas gesturus sum, vadem praedemque habeo, Curt. 9, 2, 25.