countermine

Etymology
From.

Noun

 * 1) A mine used by defenders to intercept an enemy mine or tunnel.
 * 2) An underground gallery excavated to intercept and destroy the mining of an enemy.
 * 3) A stratagem or plot by which another stratagem or project is defeated.
 * 1) A stratagem or plot by which another stratagem or project is defeated.

Verb

 * 1) To plot opposition; to frustrate the initiatives of another.
 * 2)  to sap hostile mining.
 * 1)  to sap hostile mining.