AAB, AaB or Aab may refer to:
Aviation
- Abelag Aviation in Belgium
- Air Assault Badge, a United States Army military badge
- Anti-aircraft battery, a weapons system component for anti-aircraft warfare
- IATA airport code for Arrabury Airport in State of Queensland, Australia
Companies and organizations
- Aalborg Boldspilklub, a sports club in Aalborg in Denmark
- AaB A/S, Aalborg Boldspilklub A/S, a Danish company
- ABN AMRO, the largest bank in the Netherlands
- Aboriginal Arts Board, an historical name for part of the Australian Council for the Arts
- Adyar Ananda Bhavan, a food business in India
- Akita Asahi Broadcasting, a television station in Akita Prefecture, Japan
- Arubaanse Atletiek Bond, the governing body for the sport of athletics in Aruba
- Athletics Association of Barbados, the governing body for the sport of athletics in Barbados
- Association of Applied Biologists, a UK-based learned society promoting applied biology
People
- Aab (surname)
- Alice Bailey, new age writer often referred to by her initials as AAB
- Akbar Al Baker, Qatar Airways CEO often referred to by his initials as AAB
Other uses
- .aab, the filename extension for Android App Bundles
- aab, the ISO 639-3 code for the Alumu language, a Niger–Congo language of Nigeria
- Acetic acid bacteria, classified under alphaproteobacteria which are used in making vinegar
- Aniline Yellow or aminoazobenzene
- Bar form, a musical form of the pattern AAB
- Antigua and Barbuda, a Caribbean country