No-fly zone
A no-fly zone, also known as a no-flight zone (NFZ), or air exclusion zone (AEZ), is a territory or area established by a military power over which certain aircraft are not permitted to fly. Such zones are usually set up in an enemy power's territory during a conflict for humanitarian or military reasons without consent of the enemy state, similar in concept to an aerial demilitarized zone, and usually intend to prohibit the enemy's military aircraft from operating in the region.