Countermine

n.	1.	(Mil.) An underground gallery excavated to intercept and destroy the mining of an enemy.
	2.	A stratagem or plot by which another sratagem or project is defeated. Thinking himself contemned, knowing no countermine against contempt but terror. - Sir P. Sidney.
v. t.	1.	(Mil.) To oppose by means of a countermine; to intercept with a countermine. [imp. & p. p. Countermined; p. pr. & vb. n. Countermining.]
	2.	To frustrate or counteract by secret measures.
v. i.	1.	To make a countermine or counterplot; to plot secretly. 'Tis hard for man to countermine with God. - Chapman.

Noun	1.	countermine - (military) a tunnel dug to defeat similar activities by the enemy
Verb	1.	countermine - destroy property or hinder normal operations; "The Resistance sabotaged railroad operations during the war" Synonyms: sabotage, undermine, weaken, subvert, counteract
	2.	countermine - destroy enemy mines with one's own mines; "We countermined the banks of the river"

abri, angle, approach trench, brew, bunker, cabal, collude, communication trench, complot, concoct, connive, conspire, cook up, counterplot, coupure, ditch, double sap, dugout, engineer, entrenchment, finagle, finesse, fire trench, flying sap, fortified tunnel, fosse, foxhole, frame, frame up, gallery, hatch, hatch a plot, hatch up, intrigue, lay a plot, machinate, maneuver, mine, moat, operate, parallel, plot, rig, sap, scheme, slit trench, trench, tunnel, wangle