Refers to the idiots who instantly merge into the fast lane as soon as they get on the highway. They proceede to drive under the speed limit as to piss off the people who want to go faster then them as if they will win a trophy for slowing down as many people as they possibly can. When the oportunity comes to merge into the middle lane they "sit" and wait till the person behind them trys to pass and then move over just to get in front of them again, sometimes causing accidents and making a lot of people mad.
Damn, Im late for work and it seems as if everyone is a left lane sitter today.
by j2shea July 10, 2011
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