| Name | Kind | Description |
| what | operation | |
| what | operation | the base class of all exceptions thrown by the standard library |
| when to query | use case diagram | |
| wiring | relation | |
| WiringDescriptor | class | |
| WiringTable | class | |
| wiringTemplate | relation | |
| wish | artifact | LocatingPin representing a low-priority directive by the user, to be fulfilled only if possible (and after satisfying the more important LocatingPins) |
| Wish | class | |
| write_buffer | relation | |
| WriteBuffer | class | |
| WriteBufferPool | class |