Ultimatum

Ul′ti‐ma″tum (–tŭm), n.; pl. E. Ultimatums (#), L. Ultimata (#). [NL. See Ultimate.] A final proposition, concession, or condition; especially, the final propositions, conditions, or terms, offered by either of the parties in a diplomatic negotiation; the most favorable terms that a negotiator can offer, the rejection of which usually puts an end to the hesitation.