Definition of je ne sais quoi
: something (such as an appealing quality) that cannot be adequately described or expressed <a young actress who has a certain je ne sais quoi>
Examples of je ne sais quoi in a sentence
Although the sculpture had flaws, it also had a certain je ne sais quoi that made it very appealing.
Origin and Etymology of je ne sais quoi
French, literally, I know not what
First Known Use: circa 1656
JE NE SAIS QUOI Defined for English Language Learners
Definition of je ne sais quoi for English Language Learners
: a pleasant quality that is hard to describe
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