Acronym for: I DON"T EVEN FUCKING KNOW (most of the times said when really frustrated, or over whelmed, or pummeled with questions, that you don't even fucking know the answers to.)
Jacky: "Why hasn't he called you? Do you think your bf is mad at you? Sam, Sam, Sam... whatcha gonna doabout it???? HUH?!? I think he's gonna break up with you... what are you gonna do?!?
Sam: "IDEFK!!!!!!!"
A variation of idk or idek, which represents a shorthand version of the phrase "I don't even know, I don't evenfucking know" Used to express a more profound sense of bewilderment and confusion.