Words at Play : 2014 Word of the Year
A television commercial shows two men eating Sonic chicken wings, one of whom states that the delicious wings will become his new "wingman" for dating, making him irresistible. His friend is skeptical: "Oh, right, gonna give you that certain je ne sais quoi?" The first man misunderstands and demands: "Jenna said what?"
Je ne sais quoi is an expression that means "a pleasant quality that is hard to describe." In French, the phrase literally means "I know not what." It's used as a noun in English, and, as is often the case with French phrases, is a fancy way of saying what one wants to say.