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 of ultimatum

• demand
• request
• requirement

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

This can trigger jealousy, possessiveness, taboo-like attractions, emotional ultimatums, social power plays or money issues that reveal deeper conflicts. —Valerie Mesa, PEOPLE, 17 June 2026

Having trekked the territory with his trusty surveyor’s compass, and in the absence of anyone else rash enough to do it, Washington volunteers to deliver an ultimatum to the encroaching French forces. —James Parker, The Atlantic, 16 June 2026

Lobby groups on May 21 issued a 40-day ultimatum to the government to act or face nationwide protests. —ABC News, 1 June 2026

When layabout postman Jesper gets assigned to the frozen town of Smeerensburg with an ultimatum to process 6,000 letters, a reclusive toymaker might be his only hope. —K. Thor Jensen, PC Magazine, 15 May 2026

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