Backtrack

Noun

 * 1) the act of backtracking

Verb

 * 1) to retrace one's steps
 * I dropped my sunglasses and had to backtrack to find them.
 * 1) to repeat or review work already done
 * If we backtrack through this problem, maybe we can figure out where we went wrong.
 * 1)  To taxi down an active runway in the opposite direction to that being used for takeoff
 * Speedbird One: Enter and backtrack Runway 27 Left