AAC is an acronym for

• Advanced Audio Coding
  • an enhanced derivative is known as HE-AAC or aacPlus
• the American Airlines Center
• Advanced Aircraft Corp
• Aerostar Aircraft Corp
• Agility Association of Canada
• Aircraft Acquisition Corp
• the Aluminum Anodizers Council
• American Aircraft Corp
• American Anglican Council
• American Aviation Corp
• Amphibian Airplanes of Canada
• the Army Air Corps of the British Army
• Associação Académica de Coimbra (Coimbra's Academic Association)
• Ateliers Aéronautiques de Colombes
• Augmentative and Alternative Communication
• Australian Aircraft Consortium
• Adaptec AdvancedRAID Controller