American Hospital Association 
American Heart Association 
Accelerated Hub Architecture 
American Humane Association 
Australian Hotels Association 
Activity Hazard Analysis 
Advanced Hardware Architectures 
African Humanitarian Action 
alert holding area 
alpha-hydroxy acid 
American Homebrew Association 
American Hyperlexia Association 
anterior hypothalamic area 
autoimmune hemolytic anemia 
acetohydroxamic acid 
acquired hemolytic anemia 
activity hazards analysis 
Adaptec Host Adapter 
Advanced Hardware Architects 
African Heritage Army 
Age-Hardenable Alloy 
Aim High Academy 
Air Alpha Greenland 
Airco Hydrogen-Atmosphere 
Aldrich humic acid 
Alpha-hydroxy acids 
American Hardboard Association 
American Heart Association's 
American Hereford Association 
American Hippotherapy Association