ULTIMATUM

ultimatum (<<schwa>>l-t<<schwa>>-may-t<<schwa>>m), n. The final and categorical proposal made in negotiating a treaty, contract, or the like. • An ultimatum implies that a rejection might lead to a break-off in negotiations or, in international law, to a cessation of diplomatic relations or even to war. Pl. ultimatums.
[Blacks Law 8th]