APA
- A-P-A Transport Corp.
- APA Corporation
- APA Group (Australia)
- APA Group (Japan)
- APA style
- APA – The Engineered Wood Association
- Ab (Semitic)
- Aborigines Progressive Association
- Acolytes Protection Agency
- Adirondack Park Agency
- Administrative Procedure Act
- Administrative Procedure Act (Switzerland)
- Advance pricing agreement
- Advance provisioning allowance
- Agency for the Performing Arts
- Aldosterone-producing adenoma
- All Peoples' Association
- All points addressable
- Allied Pilots Association
- Amateur press association
- American Payroll Association
- American Philological Association
- American Philosophical Association
- American Planning Association
- American Polygraph Association
- American Poolplayers Association
- American Poultry Association
- American Protective Association
- American Psychiatric Association
- American Psychological Association
- American pale ale
- Americanist phonetic notation
- Amplified piezoelectric actuator
- Anderson Preparatory Academy
- Anglican Province of America
- Antarctic Protected Area
- Apa (footballer)
- Apa (ship)
- Apa Sherpa
- Apa of Slavonia
- Apa, Acıpayam
- Apa, Benue
- Apa, Lagos
- Apa, Satu Mare
- Apache Railway
- Approved Publication Arrangement
- Army Prosecuting Authority
- Asian Pacific American
- Asian Pickleball Association
- Asset purchase agreement
- Association of Panamerican Athletics
- Association of Publishing Agencies
- Atypical polypoid adenomyoma
- Austin Peace Academy
- Australian Parkour Association
- Australian Postgraduate Awards
- Australian Progressive Alliance
- Austria Press Agency
- Azerbaijan Press Agency
- Bronze Age sword
- Centennial Airport
- Father (1966 film)
- Japan Advertising Photographers' Association
- KJ Apa
- List of United States Navy amphibious warfare ships
- Member of the European Parliament
- NSDAP Office of Foreign Affairs
- Peruvian Astronomy Association
- Southern Athabaskan languages
- The Hong Kong Academy for Performing Arts
- Upu