“Je Ne Sais Quoi” By Deane Barker • January 15, 2022 • French for “I don’t know what.” It means some quality that you find appealing, but cannot describe in words. Why I Looked It Up I think it came up in a YouTube video was watching. I sort of knew what it meant from inflection – when people say it, they get all wistful about it, and they’re usually talking about a female attraction.