je ne sais quoi*: Meaning and Definition of

je ne sais quoi

Pronunciation: (zhun se kwa'), [key]
— French. French.
  1. an indefinable, elusive quality, esp. a pleasing one:je ne sais quoi that charms everybody. She has a certain
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.