AAC may refer to:

In aviation:

• IATA airport code for El Arish International Airport, Egypt
• Advanced Aircraft Corporation, an aircraft manufacturer based in Carlsbad, California
• American Aviation Corporation, an aircraft manufacturer based in Cleveland, Ohio
• Alaskan Air Command, a radar network
• Enea Bossi, Sr.#American Aeronautical Corporation, an aircraft designer and manufacturer
• Amphibian Airplanes of Canada, a developer and marketer of light amphibious aircraft based in Squamish, British Columbia

In camping:

• Association of Alabama Camps, an association that represents the interests of the children and families who attend camps in Alabama, as well as the camps themselves.

In computing:

• Advanced Audio Coding, an audio compression format specified by MPEG-2 and MPEG-4, and successor to MPEG-1’s “MP3” format.

In education and communication:

• Associação Académica de Coimbra, the students' union of the University of Coimbra
• Augmentative and alternative communication, an area of research, clinical, and educational practice

In military contexts:

• Airborne aircraft carrier, an aircraft which can launch other aircraft
• Army Air Corps (United Kingdom), a component of the British Army
• Army Apprentices College, a college that offered military training, education and common core skills
• Australian Army Cadets, a youth organisation that is involved with progressive training of youths in military and adventurous activities
• Advanced Armament Corp., a suppressor manufacturer

In sports:

• American Airlines Center, an arena located near downtown Dallas, Texas
• American Alpine Club, an American organization
• Appalachian Athletic Conference, an athletic conference sanctioned by the NAIA
• Associação Académica de Coimbra - O.A.F., an autonomous and professional football organization based in Coimbra, Portugal
• Atlanta Athletic Club, a world-renowned private athletic club in Duluth, Georgia
• Audax Alpine Classic, a tough 200km bicycle event in Victoria, Australia
• Mic Mac AAC, a club that is part of CanoeKayak Canada's Atlantic Division
• Pitreavie AAC, a Scottish organization

In other fields:

• Acting Assistant Commissioner
• Aerated autoclaved concrete, a lightweight, precast building material
• Affirming Anglican Catholicism, a movement operating in several provinces of the Anglican Communion in North America
• Agility Association of Canada, a dog organization
• Alameda Arts Council, the Alameda City arts council serving the arts in the Alameda area
• American Alpine Club, the leading national organization in the United States devoted to mountaineering, climbing, and the multitude of issues facing climbers
• American Anglican Council, a conservative organization within the Episcopal Church in the United States
• Antimicrobial Agents and Chemotherapy, an academic journal published by the American Society for Microbiology
• Australian Agricultural Company, a company which serves to improve beef cattle production through responsible natural resource and land use
• Australian Aluminium Council, an industry association representing Australian bauxite mining companies and aluminium smelters.
• Auto Avio Costruzioni 815, the first Ferrari car that was fully designed and built by Enzo Ferrari