plural ultimatums or ultimata
-tə 
: a final threat : a promise that force or punishment will be used if someone does not do what is wanted
She was given an ultimatum—work harder or lose her job.
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“Ultimatum.” Merriam-Webster.com Simple Definition, Merriam-Webster, https://www.merriam-webster.com/simple/ultimatum. Accessed 23 Jun. 2026.
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