AAS

Initialism of Advanced Automation System, a system for radar control of transoceanic air corridors.

Initialism of angle-angle-side triangular congruency.

Initialism of anabolic–androgenic steroid.

Initialism of acute aortic syndrome.

Initialism of Australian Anthropological Society.

Initialism of American Arachnological Society, a society of amateur and professional arachnologists.

Initialism of American Astronautical Society, an independent scientific and technical group in the United States.

Initialism of American Astronomical Society, a United States society of professional astronomers.

Initialism of Australian Academy of Science, an independent, government-endorsed society with the aim of promoting science.

Initialism of All-America Selections, an organization that promotes development of new garden seed varieties.

Initialism of Air Ambulance Service, a UK charity.

Initialism of Assyrian Aid Society.

Initialism of American Anti-Slavery Society.

Initialism of Ansar al-Sunna, or Jamaat Ansar al-Sunna, a militant group operating in Iraq.

Initialism of American Association of Suicidology, an American nonprofit suicide prevention organization.

Initialism of Association for Academic Surgery.

Initialism of Arnold Air Society, a professional honorary service organization for Air Force officer candidates.

Initialism of Atomic Absorption Spectroscopy.

Initialism of American Antiquarian Society, an American society and national research library.

Initialism of Association for Asian Studies.

Initialism of Assyrian Academic Society.

Initialism of African Academy of Sciences, an Africa-wide scientific organization.