"Pro" cyclists-- Usually social riders, wearing lycra pants and jerseys, riding bikes worth more than a respectable motorcycle, and training on quite possibly the most inconvenient roads while people are attempting to get to work/school/home-- usually major, single lane roads-- and often not in the bike lane.

Not all "pro" (or pro-am) cyclists are bum wigglers but the ones that are, you typically find going up that tight, annoying stretch of hilly road at 15mph/20kph when you're already late for work.
That bloody Bum Wiggler with the Porsche jersey on Bridge St. showed up again. If he makes me miss the team meeting again I'm just going to run the bastard over.
by Numbers85 February 10, 2011
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