AOP
- AOP (IRC)
- AOPS (disambiguation)
- Aama Odisha Party
- Advanced oxidation process
- Adverse outcome pathway
- Age of Persuasion
- Agent-oriented programming
- Air observation post
- All one polynomial
- American Opera Projects
- Annals of Probability
- Apnea of prematurity
- Apocalypse of Peter
- Appellation d'origine protégée (Switzerland)
- Argument of periapsis
- Army of the Potomac
- Aspect-oriented programming
- Assembly of the Poor
- Association of Optometrists
- Association of Photographers
- Attribute-oriented programming
- Australian Orangutan Project
- Authors of Pain
- AŌP