afferent pupillary defect 
Army Publishing Directorate 
Avalanche Photo Diode 
APPLIED DIESEL 
Area Passive Dosimeter 
Additional Product Documentation 
advanced planning document 
air particulate detector 
Army Pay Department 
Azimuthal photoelectron diffraction 
action potential duration 
Advance Planning Document 
Air Passenger Duty 
Albuquerque Police Department 
Alternate Pump Development 
Amplitude Probability Distribution 
ANGULAR POSITION DIGITIZER 
Approach Progress Display 
Area Postal Directory 
astronaut positioning device 
auditory processing disorder 
automated peritoneal dialysis 
Automatic Power Down 
avoidant personality disorder 
Converted Destroyer 
Destroyer Escort 
Abbeville Police Department 
Abbotsford Police Department 
Aberdeen Police Department 
Abilene Police Department