a sound people make in response to an awkward, unintelligible, or odd comment or question in an attempt to sound like a pretentious prick. Used predominantly by sarcastic assholes and ditzy teenage girls
Nerdy guy: "I'm having a get-together this weekend. It would be great if I could see you there. What do you say?"
Ditzy teenage girl: "tssss, um yeeeah... I don't think so."

Girl walks away, leaving nerdy guy thinking "What a bitch."
by Zegeroth August 3, 2007
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