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sine qua non

[sahy-nee kwey non, kwah, sin-ey, si-ne kwah-nohn] / ˈsaɪ ni kweɪ ˈnɒn, kwɑ, ˈsɪn eɪ, ˈsɪ nɛ kwɑˈnoʊn /
NOUN
condition
Synonyms
WEAK
arrangement article catch codicil contingency demand essential exception exemption fine print kicker modification must must-have necessity need postulate precondition prerequisite provision proviso qualification requirement requisite reservation rule small print stipulation strings terms

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.

The image of Toyotas and Datsuns — soon rebranded as Nissans — went from quirky to sine qua non.

From Los Angeles Times • Mar. 18, 2026

This is the sine qua non of self-defense.

From The Wall Street Journal • Mar. 12, 2026

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

From Seattle Times • Mar. 18, 2023

Lowering that temperature and finding genuine solutions to the disputes that divide us is increasingly the sine qua non of American domestic statesmanship.

From Washington Post • Mar. 1, 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