From French enveloppement


envelopment ‎(plural envelopments)

  1. The act of enveloping
  2. (military) An offensive action in which an attacking force moves over or around the enemy and attacks from the rear; see also pincer movement
  3. (fencing) An action to seize the opponent's blade in one line and lead it (without losing contact) through a full circle to end in the same line