Defense Health Agency. The Defense Health Agency (DHA) is a joint, integrated Combat Support Agency that enables the U.S Army, U.S Navy, and U.S Air Force medical services to provide a medically ready force and ready medical force to Combatant Commands in both peacetime and wartime.
Definition of preemption. 1a : the right of purchasing before others; especially : one given by the government to the actual settler upon a tract of public landb : the purchase of something under this right.
A preemptive action is made to keep some other action from being taken. Before you could be accused of eating the whole cake, you decided to make a preemptive apology, which was met with awkward silence. Tired of being disturbed by your roommate's loud music, your preemptive strike was to crank up your favorite opera as soon as you arrived home. Unfortunately, he'd already made a preemptive strike of his own by borrowing your stereo. Don't confuse preemptive with peremptory, a word meaning âarrogant.â You don't have to be arrogant to make a preemptive move, just cautious.