sidetrack
noun
°A second, relatively short length of track just to the side of a railroad track, joined to the main track by switches at one or both ends, used either for unloading freight, or to allow two trains on a same track to meet (opposite directions) or pass (same direction); a railroad siding.
°(sometimes) Any auxiliary railroad track, as differentiated from a siding, that runs adjacent to the main track.
verb
°To divert (a locomotive) on to a lesser used track in order to allow other trains to pass.
°To divert or distract (someone) from a main issue or course of action with an alternate or less relevant topic or activity; or, to use deliberate trickery or sly wordplay when talking to (a person) in order to avoid discussion of a subject.
synonyms: railroad siding, siding, lay-by