| Acronym | Definition |
|---|
| UMO | Unknown Mortal Orchestra (band) |
| UMO | University of Mount Olive (North Carolina) |
| UMO | Used Motor Oil |
| UMO | University of Missouri |
| UMO | University of Maine at Orono (obsolete; now University of Maine, UM) |
| UMO | Unit Movement Officer |
| UMO | Update.mozilla.org (website) |
| UMO | Universal Message Object (MuleSource, Inc.) |
| UMO | Unit Movement Office |
| UMO | Undeliverable Mail Office (Canada Post) |
| UMO | Unmodified Molecular Orbital |
| UMO | Unconventional Military Operations |
| UMO | Useless Management Overhead |
| UMO | Unidentified Micro-particle Object (anime) |