Term | Explanation |
| Waffen SS | The branch of the SS which formed military fighting divisions. |
| Watchtower | Code name for the Guadalcanal-Tulagi Operation. |
| Wehrmacht | The German armed forces - headed by the OKW. |
| Weserubung | River Exercise - Operational code name for the German invasion of Denmark and Norway - April 1940. |
| WIA | Acronym for Wounded In Action. |
| Window | Also known as Chaff - metallic foil strips dropped from bombers to give the appearance to German radar of mass formations of aircraft. |
| Wintergewitter | Winter Storm - Operational code name for the unsuccessful German attempt to relieve the 6th Army at Stalingrad - December 1942. |
| Wolfschanze | Wolf's Lair - code name for Hitler's headquarters near Rastenburg in East-Prussia. |
| WPD | War Plans Department (US). |