| T&O | Test and Operations
| Others |
| T&O | Trauma and Orthopaedics
| Others |
| T.O | Timed Out
| Others |
| T.O. | Top Of
| Others |
| T/O | Table of Organization
| Others |
| T/O | Takeover
| Others |
| T/O | Theater of Operations
| Others |
| T/O | Top Off
| Others |
| T/O | Train Operator
| Others |
| TO | Operations Management (KSC Directorate)
| Others |
| TO | Operations Management (TS)
| Others |
| TO | Tal Observation
| Others |
| TO | Task Order
| Others |
| TO | Technical Order
| Others |
| TO | Terrell Owens
| Others |
| TO | The Opera
| Others |
| TO | Tonga
| Others |
| TO | Torino (Province)
| Others |
| TO | Toronto, Ontario, Canada
| Others |
| TO | Total Outburst
| Others |
| TO | Totally Obligated
| Others |
| TO | Totally Obtuse
| Others |
| TO | Tournament Organiser
| Others |
| TO | TracheOesophageal
| Others |
| TO | Traffic Officer
| Others |
| TO | Training Officer
| Others |
| TO | Transistor Outline package
| Others |
| TO | Transportation Office(r)
| Others |
| TO | Transportation Officer
| Others |
| TO | Transportaton Officer
| Others |
| TO- | Total Observation
| Others |