ultimatum

noun

ul·​ti·​ma·​tum ˌəl-tə-ˈmā-təm  -ˈmä- 

plural ultimatums or ultimata ˌəl-tə-ˈmā-tə 

-ˈmä-

: a final proposition, condition, or demand

especially : one whose rejection will end negotiations and cause a resort to force or other direct action

Synonyms

• claim
• demand
• dun
• importunity
• requisition

Examples of ultimatum in a Sentence

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

Recent Examples on the Web

Trump also set a new ultimatum for Putin, issuing a deadline to reach a ceasefire deal. —Caitlin McFall, FOXNews.com, 29 Apr. 2025

The administration’s war with Harvard, too, was launched in haste and (by the administration’s own account) with an ultimatum letter sent by mistake. —The Editors, National Review, 29 Apr. 2025

Many enterprises often consider checking boxes as the ultimatum, wherein the nuances of each compliance control get overlooked. —Siranjeevi Dheenadhayalan, Forbes.com, 28 Apr. 2025

Later that day, Kirkland & Ellis gave Clement a by now familiar ultimatum: give up his gun clients or leave the firm. —Ruth Marcus, New Yorker, 25 Apr. 2025

Word History

Etymology

New Latin, from Medieval Latin, neuter of ultimatus final

First Known Use

1731, in the meaning defined above

Rhymes for ultimatum

• latum
• verbatim

Kids Definition

ultimatum

noun

ul·​ti·​ma·​tum ˌəl-tə-ˈmāt-əm  -ˈmät- 

plural ultimatums or ultimata -ə 

: a demand that if rejected will bring about an end of peaceful talks and could lead to forceful action