Mil. [F. écoute (f. écouter to listen) an excavation, in which a miner can listen for the working of the enemy’s miners.] (See quot.)
1815. Hutton, Phil. & Math. Dict., I. 282. Catacoustics,… are écoutes or small galleries … in front of the glacis of a fortified place, all of which communicate with a gallery that is carried parallel to the covert-way.
