sine qua non

Use the expression sine qua non as an impressive way of describing something that's essential.

Chocolate chips are the sine qua non of chocolate chip cookies, for example, and wind is a sine qua non for flying a kite. The term literally means "without which not" in Latin, and it was originally a legal term. These days, it's used more generally to talk about anything that's necessary.

Definitions of sine qua non
  1. noun
    a prerequisite
    synonyms: essential condition
    see moresee less
    type of:
    prerequisite, requirement
    something that is required in advance
Word Family
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