1. countermarch - Noun
2. countermarch - Verb
To march back, or to march in reversed order.
A marching back; retrocession.
An evolution by which a body of troops change front or reverse the direction of march while retaining the same men in the front rank; also, a movement by which the rear rank becomes the front one, either with or without changing the right to the left.
A change of measures; alteration of conduct.
Source: Webster's dictionary