abnormal anaphase resolution 
accelerated acute rejection 
Accredited in Appraisal Review 
accumulation-area ratio 
Active Antenna Radar 
Active Array Radar 
active avoidance reaction 
acute articular rheumatism 
adaptive autoregressive 
Administrative Adjustment Report 
Adobe Acrobat Reader 
Advanced Address Recognizer 
affirmative action representative 
After Action Report 
After Action Reports 
After Action Review 
After Action Reviews 
After-Action Review 
Against All Risks 
Air alert range 
Air America Radio 
Air Augmented Rocket 
Air to Air Refueling 
Air to Air Refuelling 
Air to Air Role 
Aircraft Accident Report 
Aircraft Accident Reports 
Aircraft Availability Rate 
Airport Acceptance Rate 
Airport Arrival Rate