The Collaborative International Dictionary of English v.0.48:

Countermarch \Coun`ter*march"\ (koun`t?r-m?rch"), v. i. [imp. &
   p. p. Countermarched (-m?rcht"); p. pr. & vb. n.
   Countermarching.] (Mil.)
   To march back, or to march in reversed order.
   [1913 Webster]

         The two armies marched and countermarched, drew near
         and receded.                             --Macaulay.
   [1913 Webster]