The Collaborative International Dictionary of English v.0.48:
Reversing \Re*vers"ing\, a. Serving to effect reversal, as of motion; capable of being reversed. [1913 Webster] Reversing engine, a steam engine having a reversing gear by means of which it can be made to run in either direction at will. Reversing gear (Mach.), gear for reversing the direction of rotation at will. [1913 Webster]