unless

[ uhn-les, uh n- ]

/ ʌnˈlɛs, ən- /

SEE MORE SYNONYMS FOR unless ON THESAURUS.COM

conjunction

except under the circumstances that: I'll be there at nine, unless the train is late.

preposition

except; but; save: Nothing will come of it, unless disaster.

Nearby words

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; see on, less

Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

Examples from the Web for unless

Unless there is a court decision that changes our law, we are OK.
Jeb Bush’s Unseen Anti-Gay Marriage Emails|Jackie Kucinich|January 9, 2015|DAILY BEAST
In some ways I never got out of that unless realizing… well, that kind of seals it off.
The Story Behind Lee Marvin’s Liberty Valance Smile|Robert Ward|January 3, 2015|DAILY BEAST
Unless Cuba sends them back, you might consider following the now lifted embargo with your own personal boycott.
Cuba Protects America’s Most Wanted|Michael Daly|December 18, 2014|DAILY BEAST
Unless you were in China on November 11, you might have missed it.
Alibaba’s Dark Side: Censoring Customers|Brendon Hong|November 18, 2014|DAILY BEAST

Unless there is “a clear national security or law enforcement need,” the bias would lean toward disclosure.
How Obama Endangered Us All With Stuxnet|Kim Zetter|November 13, 2014|DAILY BEAST
Unless they give satisfaction thai schul be depper dampned then Judas Scarioth.
A History of The Inquisition of The Middle Ages; volume II|Henry Charles Lea
I have put myself out of sorts for the day, and shall go and walk, unless the direction of this sets me up again.
The Letters of Charles Dickens|Charles Dickens
I expect to know very shortly; and the moment I know I will try to inform you, unless I am forbidden.
The Mystery of the Sea|Bram Stoker
Eagle-head saw that, unless he made a desperate effort, he would be lost, and he attempted it.
The Tiger-Slayer|Gustave Aimard
I shan't see you again for ever so long, Yorick, unless you and Bessy change your minds and come up earlier.
It Never Can Happen Again|William De Morgan

British Dictionary definitions for unless

unless

/ (ʌnˈlɛs) /

conjunction

(subordinating) except under the circumstances that; except on the condition thatthey'll sell it unless he hears otherwise

preposition

rare except

Word Origin for unless

C14: onlesse, from on on + lesse less; compare French à moins que, literally: at less than

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

Word Origin and History for unless

unless

conj.

mid-15c., earlier onlesse, from on lesse (than) "on a less condition (than)," the first syllable originally on, but the negative connotation and the lack of stress changed it to un-.