(1):
(v. i.) To make a countermine or counterplot; to plot secretly.
(2):
(n.) An underground gallery excavated to intercept and destroy the mining of an enemy.
(3):
(v. t.) To frustrate or counteract by secret measures.
(4):
(v. t.) To oppose by means of a countermine; to intercept with a countermine.
(5):
(n.) A stratagem or plot by which another sratagem or project is defeated.