PPO
- 2,5-Diphenyloxazole
- Personal Protection Officer
- Personal Protection Order
- Pfadfinder und Pfadfinderinnen Österreichs
- Philippine Philharmonic Orchestra
- Plant Phenology Ontology
- Police protection order
- Polish Patent Office
- Political Parties Order, 2002
- Poly(p-phenylene oxide)
- Polyphenol oxidase
- Populist Party Ontario
- Preferred Provider Organization
- Prisons and Probation Ombudsman
- Propylene oxide
- Protoporphyrinogen oxidase
- Proximal Policy Optimization
- Public prosecutor's office
- Purchase order
- Pure plant oil
- Toray Pan Pacific Open
- White House Presidential Personnel Office