This word is pronounced deep from the bowels of ur stomach, it should sound like a old man shivering out in the cold. It has many meanings such as howling laughter and relentless chaos. It also describes the bizarre, the criminally insane, and the downright schizophrenic. UHUHUH is simply a madman's word and shouldn't be used lightly in day-to-day conversation.
When u find out u dont have any milk for ur cinnamon toast crunch you yell out, "UHUHUHUHUHUUHUH."