To stop what your doing. As if whatever your saying or doing is stupid or ridiculous.
Lisa tried to tell me that Raheim was cheating on me but I said to the bitch, "Pump ya brakes", you don't know what the fuck you're talking about.

Tatatulisha thought she was going to pull on my weed for free. I told that ho to pump her mothafuckin brakes.
by GB April 3, 2003
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