| Acronym | Definition |
|---|
| PAO | Public Affairs Office(r) |
| PAO | Paoli (Amtrak station code; Paolia, PA) |
| PAO | Publication Assistée par Ordinateur (French: desktop publishing) |
| PAO | Periodicals Archive Online |
| PAO | Postacademisch Onderwijs (Dutch: Postgraduate Education) |
| PAO | Public Attorney's Office (Philippines) |
| PAO | Public Aircraft Operations |
| PAO | Period After Opening |
| PAO | Periacetabular Osteotomy (hip surgery) |
| PAO | Panathinaikos Athlitikos Omilos (Panathinaikos Athletic Club) |
| PAO | Public Assistance Officer (US FEMA) |
| PAO | Privacy Act Office (US DHHS) |
| PAO | Planetary Activation Organization (El Dorado Hills, CA) |
| PAO | Production Assistée par Ordinateur (French) |
| PAO | Programme Authorising Officer (EU programs) |
| PAO | Pacific Area Office |
| PAO | Pro Arte Orchestra (various locations) |
| PAO | Portland Area Office (various businesses) |
| PAO | Program Action Office (US Air Force) |
| PAO | Philippine Academy of Ophthalmology (Makati City, Philippines) |
| PAO | Polyalphaolephin |
| PAO | Provider Access Organization (healthcare) |
| PAO | Post-Award Orientation (federal contracts) |
| PAO | Poker Academy Online |
| PAO | Phased-Array Optics (nanotechnology) |
| PAO | Potencial de Agotamiento de Ozono (Spanish for ODP) |
| PAO | Project Administration Office(r) |
| PAO | Program Analysis Office |
| PAO | Phosphorus-Accumulating Organism (environmental engineering) |
| PAO | Polynesian Limited Samoa (ICAO code) |
| PAO | Property Accounting Office |
| PAO | Project Action Officer |
| PAO | Planning and Analysis Officer |
| PAO | Primary Action Officer |
| PAO | Pan-African Organization |
| PAO | Postulated Abnormal Occurrence |
| PAO | Pediatric Assessment Online |
| PAO | Phased Air Operation |
| PAO | Psychiatric Assignment Officer |
| PAO | Periodical Aromatic Odor |
| PAO | Palo Alto, California Municipal Airport (Airport Code) |
| PAO | Primary/Program Action Office(r) |
| PAO | Physical Aggression toward Others (psychology) |