Counter vallation

Webster's Practical Dictionary- A Practical Dictionary of the Englih Language · 1884 · p. 97

kown'ter-val-la's hun, n. (Fort.) A chain of redoubts around a fortre , to prevent sorties by the garrison; construction of such works. Counte . See under Count, n. Counting-house, Countle , etc. See under Count, v. t.