| Abbreviation | Definition |
|---|---|
| RUN | Running |
| RUNKIN | RUNKING |
| RUNSANE | RunSanity |
| RUNU | Risorse Umane e non Umane |
| RUO | Reference Unbundling Offer |
| RUO | Reflection for UNIX and OpenVMS |
| RUO | Repositorio de la Universidad de Oviedo |
| RUO | Resident Unit Officer |
| RUP | Random Unnamed Person |
| RUP | Rational Unified |
| RUP | Rational Unified Process® |
| RUP | Rational Unified Processing |
| RUP | Recurrent Unexplained Palpitations |
| RUP | Relational Unified Practice |
| RUP | Restricted Use Pesticides |
| RUP | Restricted Use Products |
| RUP | Rumen Undegradable Protein |
| RUP | Rural and Urban Projection |
| RUP | Rural Utah Project |
| RUPA | Retired United Pilots Association |