ultimatum

American  

[uhl-tuh-mey-tuhm, -mah-] / ˌʌl təˈmeɪ təm, -ˈmɑ- /

noun

ultimatums, plural ultimata plural

1. a final, uncompromising demand or set of terms issued by a party to a dispute, the rejection of which may lead to a severance of relations or to the use of force.

2. a final proposal or statement of conditions.

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ultimatum British  

/ ˌʌltɪˈmeɪtəm /

noun

1. a final communication by a party, esp a government, setting forth conditions on which it insists, as during negotiations on some topic

2. any final or peremptory demand, offer, or proposal

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ultimatum Cultural  

1. A formal message delivered from one government to another threatening war if the receiving government fails to comply with conditions set forth in the message. For example, after the assassination of the Archduke Francis Ferdinand in 1914, the government of Austria sent an ultimatum to Serbia, which Austria held responsible for the assassination.

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Other Word Forms

Noun Inflected Forms

• ultimata
  plural
• ultimatums
  plural

Etymology

Origin of ultimatum

First recorded in 1725–35; from New Latin, noun use of neuter of Late Latin ultimātus “ended, finished,” past participle of ultimāre “to come to an end”; see ultimate

Explanation

An ultimatum is a final demand attached to a threat, like "If you don't do it, I'll never speak to you again." Ultimatums are serious business. The noun ultimatum has Latin roots meaning "final" and that's still what the word means today. It is the final demand, usually with an implicit or explicit "or else" attached to it. Often, the person on the receiving end of the ultimatum rebels, however, and will say something like, "Don't give me any ultimatums!"

Example Sentences

The ultimatum has no legal backing but has gained traction through countrywide protests, threats at places where foreigners live or work, and a toxic social media campaign that analysts say has been building for years.

From Barron's • Jun. 19, 2026

But they also issued an ultimatum: “If we can continue doing the work that made this show what it is—committing acts of independent, fearless journalism and storytelling—we’re here for it. If not, we leave.”

From Slate • Jun. 5, 2026

His extension last week of an ultimatum on attacking Iranian energy infrastructure did nothing to calm markets, and investors seem to be reacting less to his comments than to tangible news from the Persian Gulf.

From MarketWatch • Mar. 29, 2026

Activist groups, calling themselves Gen Z and Gen Y movements, had recently issued a 72-hour ultimatum for Randrianirina's resignation, citing frustration with his performance, local media reported.

From BBC • Mar. 10, 2026

I issued an ultimatum: we have to leave, there’s no way I can stay in this house, on this road, knowing everything that has gone on here.

From "The Girl on the Train" by Paula Hawkins

Related Words

• warning