Definitions
1.verbTo retrace one's steps."I dropped my sunglasses and had to backtrack to find them."
2.verbTo repeat or review work already done."If we backtrack through this problem, maybe we can figure out where we went wrong."
3.verbTo taxi down an active runway in the opposite direction to that being used for takeoff."Speedbird One: enter and backtrack Runway 27 Left."
4.verbTo exercise a racehorse around the racetrack in the opposite direction to that in which races are run.
5.noun(countable, uncountable) The act of one who, or that which, backtracks; a retracing of one's steps.
6.nounThe usage of a runway as a taxiway, especially at private strips and smaller airports.
7.nounThe act of building all possible solutions to a problem incrementally, abandoning any candidate solution if it cannot lead to a valid solution.