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Synonyms

unless

American  
[uhn-les, uhn-] / ʌnˈlɛs, ən- /

conjunction

  1. except under the circumstances that.

    I'll be there at nine, unless the train is late.


preposition

  1. except; but; save.

    Nothing will come of it, unless disaster.

unless British  
/ ʌnˈlɛs /

conjunction

  1. (subordinating) except under the circumstances that; except on the condition that

    they'll sell it unless he hears otherwise

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

preposition

  1. rare except

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Etymology

Origin of unless

1400–50; late ME prepositional phrase on less (also o less(e) , earlier upon less ) on a lesser footing or condition (than); first used as a preposition and conjunction in the early 16th century; on, less

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

U.S. casualties and damage to American interests would be higher unless the U.S. moved first, the senior official said.

From The Wall Street Journal

And unless you’re watching some outré arthouse film allowed to play by its own rules, there’s a finite amount of time for the director to communicate the essential building blocks of their story that are necessary for the viewer’s enjoyment.

From Salon

Hughes also keenly understood that, because these personalities were so familiar, his characters wouldn’t stand out to viewers unless they pushed their paradigm.

From Salon

Her inflated self-esteem is a force of nature never wielded unkindly, unless provoked.

From Salon

Druckenmiller said that, given his family office’s long exposure to lots of risk assets, it’s keeping a short position in bonds, which wouldn’t be a big moneymaker unless he’s right and the economy sees disinflationary growth.

From MarketWatch