The Collaborative International Dictionary
Countermured
Countermure \Coun`ter*mure"\ (koun`t?r-m?r"), v. t. [imp. & p.
p. Countermured (-m?rd"); p. pr. & vb. n. Countermuring.]
To fortify with a wall behind another wall. [R.]
--Kyd.
Wiktionary
countermured
vb. (en-past of: countermure)