countermure UK /ˈkaʊntəˌmjʊə/US /ˈkaʊntɚˌmjʊɹ/noun 1verb 1forms 3 noun1 •A wall raised behind another, to supply its place when that is breached or destroyed.if they could aduance a countermure as high as their wals , and so to attaine to the conquest thereof — 1603 verb1 •To fortify with a wall behind another wall.15??, Thomas Kyd, The Spanish Tragedy They are plac'd in those empyreal heights, Where, counter-mur'd with walls of diamond, I find the place impregnable. formscountermured · countermuring · countermures