To march back.Milit., to execute a countermarch. See countermarch, n., 2.n. A marching back; a returning.n. Milit., a change of the wings or face of a body of men, so as to bring the right to the left or the front to the rear, and retain the same men in the front rank: or a rear rank may become a front rank by countermarching round the end of the latter, which remains stationary.n. Figuratively, a complete change or reversal of measures or conduct.