A traffic lane intended for some other purpose, such as turning or exiting, but used for "me-firsting" by a motorist.
A me-firsting lane can be any of the following:
1.) A turning lane when used to go straight. The motorist gets into that lane (which is clear), goes faster than the speed of others in the congested "straight" lane, and then sneaks in in front of another vehicle s/he was previously behind in order to get ahead in traffic and possibly make a light.
2.) An upcoming exit or merge lane used to pass slowed traffic on a highway, then sneak back into the lane where one previously was, but ahead of one or more vehicles.