a slut, only in that it sounds like you are saying "What?", as if you were asking a question. Great for when there are teachers around and you already have five detentions under your belt!
Guy 1: Hey, look at that girl with all those guys, I bet she's gonna get a flogging tonight!
Guy 2: That's becuase she's a Swhat!
Naive Teacher: Wha? Oh, okay, never mind.