| Abbreviation | Definition |
|---|---|
| PSEU | Public Service Executive Union |
| PSN | Pharmaceutical Society of Nigeria |
| PSNU | Partially Stiff Non Unions |
| PSSU | Pennsylvania Social Services Union |
| PSSU | Political Science Student Union |
| PSU | Professional Skaters Union |
| PSU | Public Sector Union |
| PSUPT | Pochury Students Union Phek Town |
| PSWU | Private Security Workers Union |
| PSWU | Public Sector Workers Union |
| PSWU | Public Service Workers Union |
| PSWU | Public Services Workers Union |
| PTEU | Plumbing Trades Employees Union |
| PTI | Pakistan Tahriq-e-Insaf |
| PTU | Pro Tri Union |
| PU | Personal Union |
| PUC | Pacific Union College |
| PUCL | People Union for Cultural Liberty |
| PUCL | People's Union for Civil |
| PUCL | People's Union for Civil Liberties |