AAI may refer to: Business AAI Corporation, a United States defense company Adam Aircraft Industries, a United States company Ahrens Aircraft Inc, an aircraft manufacturer established at Oxnard, California American Athletic Inc., an athletic apparel brand owned by Fruit of the Loom Arlington Asset Investment, a real estate investment trust headquartered in Arlington, Virginia AutoAlliance International, a joint-venture automobile assembly firm co-owned by Ford and Mazda Aviation Industries Ilyushin, a Russian company Non-profit organizations Adım Adım Initiative, a volunteer-based social initiative in Turkey that promotes charitable giving Africa-America Institute, an international organization dedicated to increasing educational opportunity for young Africans and improving global understanding of Africa AIESEC Alumni International, an international project of association for former volunteer members, executive boards, international trainees or staff of AIESEC Airline Ambassadors International, a non-profit organization American Antitrust Institute, an independent Washington-based non-profit education, research, and advocacy organization American Association of Immunologists, a non-profit organization dedicated to advancing the field of immunology Arab American Institute, a non-profit organization based in Washington D.C. that focuses on the issues and interests of Arab-Americans nationwide Architectural Association of Ireland, an organisation dedicated to architecture Asian Arts Initiative, a non-profit organization in Philadelphia Atheist Alliance International, a global network of atheist organizations around the world Education Alliance Academy International, an international school following an American curriculum in Quito, Ecuador Andreyev Acoustics Institute, a Russian research facility dedicated to the study of acoustics Africa-America Institute, CIA run education organisation Technology AAI, IATA airport code for Arraias Airport in Arraias, Tocantins, Brazil AAI Sparrowhawk, an American two seat pusher ultralight autogyro, available in kit form for amateur construction AAI Corporation Aerosonde, a small unmanned aerial vehicle (UAV) designed to collect weather data over oceans and remote areas AAI underwater revolver, an amphibious firearm intended for naval use Authentication and authorization infrastructure, access-control for network content Science Alpha amylase inhibitor, a group of proteins that blocks the Enzyme Alpha-Amylase AAI mode of an artificial pacemaker: Atrial chamber paced, Atrial chamber sensed, and Inhibiting response to sensing Atlantoaxial instability, caused by laxity of the transverse ligament of atlas, a ligament which arches across the ring of the atlas (the topmost cervical vertebra, which directly supports the skull) Entertainment Aai (film), an Indian Tamil language film starring R. Sarath Kumar, Namitha Kapoor, Vadivelu, Kalabhavan Mani AAI (album), 2021 album by Mouse on Mars Ace Attorney Investigations: Miles Edgeworth, a 2009 spin-off video game