Anglo-Australian Telescope 
Ambient Air Temperature 
Association of Accounting Technicians 
Arc Attribute Table 
atomic axial tensor 
Average Access Time 
Activation Acceptance Team 
Apple Advanced Typography 
Army Assault Team 
Art and Architecture Thesaurus 
Aspartate AminoTransférase 
Associate of Applied Technology 
Associate of Arts in Teaching 
Association Of Accounting Technicians 
aachen aphasia test 
abdominal adipose tissue 
ablation therapy 
academic aptitude test 
acceleration test 
acetic acid test 
acid acyltransferase 
acute acoustic trauma 
ADP/ATP translocase 
advanced academic training 
Advanced Analytic Tools 
Advanced Antenna Technology 
Advanced Armament Technology 
Advanced Authoring Tools 
air-assault task 
Airport Authority of Thailand