/kon'treuh veuh lay"sheuhn/ , n. Fort.
a more or less continuous chain of redoubts and breastworks raised by besiegers outside the line of circumvallation of a besieged place to protect the besiegers from attacks from the outside, as by a relieving force.
[ 1670-80; CONTRA- 1 + VALLATION; cf. F contrevallation, It contravvallazione ]