1. Airborne – A general locality between the mounting area and the objective of an airborne expedition through which the expedition, or parts thereof, pass after mounting, for refueling; regrouping; and/or exercise, inspection, and redistribution of troops. 2. Other movements – A general locality established for the concentration of troop units and transient personnel between movements over the lines of communications. 3. In amphibious operations, one or more intervening ports for refueling, logistic support, emergency repairs, or final rehearsals. Also called SA.