| TC | Tank Corps |
| TCO | Train Conducting Officer |
| TDO | Telephone Dug-out |
| TEE | Tyne Electrical Engineers |
| TF | Territorial Force |
| TM | Trench Mortar |
| TMB | Trench Mortar Battery |
| TO | Transport Officer |
| TOS | Taken on strength |
| TR | Training Reserve |
| TRB | Training Reserve Brigade |
| TRIMMER | Part of a Ships crew |
| Trinity | Holy Trinity Church memorial |
| TSM | Troop Sergeant Major (cavalry) |
| UB | German submarine - Underwater boat |
| VAD | Voluntary Aid Detachment |
| VADGS | Voluntary Aid Detachment General Service |
| VC | Victoria Cross awarded |
| VO | Veterinary Officer |
| VTC | Volunteer Training Corps |
| WD | War Department |
| WE | War Establishment |
| WIR | West India Regiment |
| WO | War Office |
| WWCS | Walking Wounded Collecting Station |