sine qua non

American  

[sahy-nee kwey non, kwah, sin-ey, si-ne kwah-nohn] / ˈsaɪ ni kweɪ ˈnɒn, kwɑ, ˈsɪn eɪ, ˈsɪ nɛ kwɑˈnoʊn /

noun

1. an indispensable condition, element, or factor; something essential.

   Her presence was the sine qua non of every social event.

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sine qua non British  

/ ˈsaɪnɪ kweɪ ˈnɒn /

noun

1. an essential condition or requirement

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sine qua non Cultural  

1. The essential, crucial, or indispensable ingredient without which something would be impossible: “Her leadership was the sine qua non of the organization's success.” From Latin, meaning “without which nothing.”

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sine qua non Idioms  

1. An essential element or condition, as in A perfect cake is the since qua non of a birthday party. This phrase is Latin for “without which not” and has been used in English since about 1600. It appears more in writing than in speech.

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Etymology

Origin of sine qua non

From Late Latin sine quā (causā) nōn “without which (thing) not”

Example Sentences

In fact, the history of whaling on its own disproves the central point of “The Killing Age,” that guns were a sine qua non for the making of the modern world.

From The Wall Street Journal • Nov. 14, 2025

From sine qua non of American psychedelia, to folk-rock deity, jam band progenitor, disco Dead and Top 40 sensation, there was seemingly no pivot the band couldn’t navigate in its 30 years.

From Los Angeles Times • Oct. 3, 2023

“Ernest & Celestine: A Trip to Gibberitia” is the gem of a sequel to that Oscar-nominated film, centering the story this time around on music as the sine qua non of community.

From New York Times • Aug. 31, 2023

And in gourmet circles, nettles are the sine qua non of spring greens.

From Seattle Times • Mar. 18, 2023

It was as though he knew very well that in Lombard's past actions legality had not always been a sine qua non....

From "And Then There Were None" by Agatha Christie