| Abbreviation | Definition |
|---|---|
| TWT | Tuesday, Wednesday, Thursday |
| UDF | Universal Date Format |
| UND | United Nations Day |
| UO | unoriginal |
| VD | Valentine's Day |
| VDAY | Valentine's Day |
| VEDAY | Victory in Europe Day, May 8 |
| VG/F | Very Good Obverse, Good Reverse |
| VJDAY | Victory over Japan Day, August 14 |
| VSDAY | Victory over Spain Day, December 10 |
| W | Wednesday |
| WAOD | World AIDS Orphan's Day |
| WB | Week Beginning |
| WBDF | World Blood Donor Day |
| WBW | Wacky Business Wednesday |
| WC | Week Commencing |
| WCFD | World Car Free Day |
| WCRD | World Consumer Rights Day |
| WDCD | World Day to Combat Desertification and Drought |
| WDCL | World Day for Consecrated Life |