| Pine Bluff Observatory | Academic & Science |
| Projected Benefit Obligation | Accounts and Finance |
| Paraburdoo | Airport Code |
| Partner Business Organization | Business |
| Performance Based Organization | Business |
| People & Business OnLine | Business |
| Professional Business Owner | Business |
| Personal Banking Officer | Business |
| Piperonyl Butoxide | Chemistry |
| Portland Baroque Orchestra | Community |
| Pension Benefit Obligation | Community |
| Philosophy Blues Original | Community |
| Philharmonia Baroque Orchestra | Community |
| Power Back Off | Computer and Networking |
| Profiler Batch Output | Computing |
| Playback Orchestre | Computing |
| Policy Based Orchestration | Computing |
| Programming by Optimisation | Computing |
| Plate Boundary Observatory | Earth Science |
| Profiler Binary Output (ms Source Profiler) | File Type |
| Polarized Born Oppenheimer | General |
| Precision Boost Overdrive | General |
| Palm Beach Opera | General |
| Pixel Buffer Objects | General |
| Project Based Organisations | General |
| Pizza Border Oriented | General |
| Processing Before Output | General |
| Paperclip Bolt and Orange | General |
| Phenylene Benz Obisoxazole | General |
| Performance Based Oversight | General |
| Pixel Buffer Object | General |
| Parliamentary Budget Officials | General |
| Parliamentary Budget Office | General |
| Pinoy Box Office | General |
| Practical Boat Owner | General |
| Public Benefit Organization | General |
| Profiler binary output | General |
| Public Benefit Organisation | General |
| President Barack Obama | General |
| Profile Based Optimization | General |
| Peak Back Off | General |
| Public Benefit Organizations | General |
| Promo Bags Online | General |
| Process Before Output | General |
| Pink Bob Omb | General |
| Packed By Owner | Governmental |
| Parliamentary Budget Officer (Canadian federal gov't) | Governmental |
| Personal Business Objective | Jobs |
| Pharmacy Benefits Optimizer | Medical |
| Pin Bones Out | Medical |
| Pin Bone Out | Medical |
| Permanent Balloon Occlusion | Medical |
| placebo | Medical |
| Property Book Officer | Military and Defence |
| Particle Beam Optics | Physics Related |
| Paraburdoo, Western Australia, Australia | Regional |
| Palos Baseball Organization | Sports |