AAO

AAO, AAo or aao may refer to:

Organizations

• Administrative Appeals Office, an office within United States Citizenship and Immigration Services
• American Academy of Ophthalmology
• American Academy of Optometry
• American Academy of Osteopathy
• American Association of Orthodontists

Places

• Anaco Airport (IATA code AAO), Anaco, Venezuela
• Andrushivka Astronomical Observatory, an observatory in Ukraine
• Australian Astronomical Observatory, an observatory in Australia
• Colonel James Jabara Airport (FAA LID: AAO), Wichita, Kansas, United States

Science and Technology

• Acer Aspire One, a subcompact notebook computer
• Alert, awake, and oriented, a measure of level of consciousness
• Amino acid oxidase, any of several enzymes
  • D-amino acid oxidase, which catalyzes D-amino acids, producing imino acids, ammonia, and hydrogen peroxide
  • L-amino-acid oxidase, which catalyzes L-amino acids, producing keto acids, ammonia, and hydrogen peroxide
• Anodic Aluminum Oxide
• Antarctic oscillation, a low-frequency mode of atmospheric variability of the southern hemisphere
• Ascending aorta (usually as "AAo")

Other uses

• aao, ISO-639-3 code for the Saharan Arabic language
• a.a.O., am angegebenen Ort, or Loc. cit. in German publications
• Aktionsanalytische Organisation, former Austrian/German commune
• America's Army, a computer game series