sine qua non

[ sahy-nee kwey non, kwah, sin-ey; Latin si-ne kwah-nohn ]

noun

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

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

sine qua non

/ ˈsaɪnɪ kweɪ ˈnɒn /

noun

1. an essential condition or requirement

sine qua non

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.”

Word History and Origins

Origin of sine qua non¹

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

Word History and Origins

Origin of sine qua non¹

literally: without which not

Idioms and Phrases

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.

Example Sentences

What I did in the meantime — because I knew that I had to be there and eat the food, and know the people, and that was sine qua non.

From Los Angeles Times

Impartiality is the sine qua non for any jurist, therefore, the privilege of a lifetime appointment requires strict avoidance of even the slightest appearance of partisanship.

From Salon

But a first hostage deal “is the sine qua non of the administration’s larger regional deal,” said Martin S. Indyk, a former U.S. ambassador to Israel.

From New York Times

For those actors who consider crying to be the sine qua non of their art, a sorrowful biography offers a distinct advantage in the Method acting sweepstakes.

From Los Angeles Times

It’s the sine qua non of public-spirited medical options, and it’s our shame and misfortune that it has been redefined by the Paxtons of this world as a strictly personal choice.

From Los Angeles Times