Is it ensure, insure, or assure?
game of Sicilian origin, popular among the ancient Greeks and to some extent in ancient Rome. In its simplest form, reclining guests attempted to throw the remains of their wine from their cups into a metal bowl; the important conditions were that no drop should be spilled in the process and that a distinct splashing noise should be made upon impact. Variations included the sinking of shallow saucers floating in a basin of water under the same conditions. Although success in cottabus required considerable skill, it contained an element of chance and was regarded as more or less indicative of the player's future success, especially in matters of love. Betting on the game was common.