F.K.I.A.
A know-it-all who thinks they’re the only one who knows anything.
My neighbor F. K. I. A. told me I was going to fail my math test before I even started it.
My friend F. K. I. A. knew the answer before I even read the question.
My mom F. K. I. A. said I’d burn down the house before I even lit a match.