Simple Definition of ultimatum
: a final threat : a promise that force or punishment will be used if someone does not do what is wanted
Examples of ultimatum
She was given an ultimatum—work harder or lose her job.
<issued the ultimatum that the project be finished by the following week, or it would be terminated>
Origin of ultimatum
New Latin, from Medieval Latin, neuter of ultimatus final
First Known Use: 1731
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