Mask

A military expre ion used in several senses. A masked battery is one so constructed with gra y glacis, etc., as to be hidden from the view of the enemy, until, to his surprise, it suddenly opens fire upon him,—on his flank, perhaps. The fire of a battery is masked when some other work, or body of friendly troops, intervenes in the line of fire, and precludes the use of the guns. A fortre or an army is masked when a superior force of the enemy holds it in check, while some hostile evolution is being carried out.