[can.is.ter] also can.nis.ter n [L canistrum basket, fr. Gk kanastron wicker basket, fr. kanna reed--more at cane] (1711) 1: an often cylindrical container for holding a usu. specified object or substance "a film ~"
2: encased shot for close-range artillery fire
3: a perforated metal box for gas masks with material to adsorb, filter, or detoxify airborne poisons and irritants