This is a sound, usually used in disgust, agrivation or disbelief. It can mean a number of things, "such as screw you", "whatever", "fuck off", or "yeah right"
MARY; OMG! I just got tickets to the concert
BARBIE: OMG! when are we going?
MARY: Well I can only bring one other person, so I picked
Suzie
BABIE: PSSHHHT, I didnt even wanna go to that concert anyway.
by Donlyone October 31, 2006
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