a: Acre
A: Alcove

a: Ampere
a: annum
a: are
a: Area
A: atto
A&D: Admission & Discharge
a&e: Accident and Emergency

A&E: Architecture and Engineering
A-D: as drawn
AA: Architectural Association
AA: Australian Aerospace
AAA: American Arbitration Association
AAA: Architects Association of Australia
AAA: Architectural Aluminium Association)
AAC: Autoclaved Aerated Concrete
AACA: Architects Accreditation Council of Australia
AACB: autoclaved aerated concrete block
AACE: American Association of Cost Engineers
AAD: Australian Academy of Design
AADT: Annual Average Daily Traffic
AAEC: Australian Atomic Energy Commission
AAFA: Assembly of Australia Fire Authorities
AAG: air arc gouging
AAH: Academy on Architecture for Health
AAHBA: Athens Area Home Builders Association
AAIB: Associate of the Australian Institute of Building
AAIBS: Associate of the Australian Institute of Building Surveyors
AAILA: Associate of the Australian Institute of Landscape Architects
AAIQS: Associate of the Australian Institute of Quantity Surveyors
AAIVLE: Associate of the Australian Institute of Valuers and Land Economists
AAM: Application Activity Model
AAMA: American Architectural Manufacturers Association
AAMA: Architectural Aluminium Manufacturers Association
AAPA: Australian Asphalt Pavement Association
AAPC: Australian Association of Planning Consultants
AAR: alkali aggregate reaction
AAS: Australian Acoustical Society
AASHTO: American Association of State and Highway Transportation Officials