Any inconsiderate asshole or bitch who "bumps" their stereo while driving by, waking you from a deep sleep, and pisses you off.
Jack: "Why are you so bitchy today?"

Jane: "I got woken up at 4:30 this morning by a drive-by bumper. Some people are so rude!"
by T0nk5_McD3an November 27, 2009
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