| xoanon | xoanon |
| Xochimilco | Xochimilco |
| Xochipilli | Xochipilli |
| Xochiquetzal | Xochiquetzal |
| Xonrupt-Longemer | Xonrupt-Longemer |
| Xoops | XOOPS |
| Xouthos | Xuthus |
| Xoïs | Xois |
| XPCOM | XPCOM |
| XPInstall | XPInstall |
| XRI | Extensible Resource Identifier |
| XScale | XScale |
| Xserve | Xserve |
| XSL-FO | XSL Formatting Objects |
| Xsp | XSP |
| XSPF | XML Shareable Playlist Format |
| Xu Chu | Xu Chu |
| Xu Yuhua | Xu Yuhua |
| Xuankongsi | Hanging Temple |
| Xuanzang | Xuanzang |
| Xun Zi | Xun Zi |
| Xuxa Meneghel | Xuxa |
| Xuzhou | Xuzhou |
| XVe corps SS de cavalerie cosaque | XVth SS Cossack Cavalry Corps |
| XVe dynastie égyptienne | Fifteenth dynasty of Egypt |
| Xvid | Xvid |
| XVIe dynastie égyptienne | Sixteenth dynasty of Egypt |
| XVIIe dynastie égyptienne | Seventeenth dynasty of Egypt |
| XVIIIe corps aéroporté américain | XVIII Airborne Corps |
| XVIIIe dynastie égyptienne | Eighteenth dynasty of Egypt |
| XXe dynastie égyptienne | Twentieth dynasty of Egypt |
| XXIe dynastie égyptienne | Twenty-first dynasty of Egypt |
| XXIIe dynastie égyptienne | Twenty-second dynasty of Egypt |
| XXIIIe dynastie égyptienne | Twenty-third dynasty of Egypt |
| XXIVe dynastie égyptienne | Twenty-fourth dynasty of Egypt |
| XXIXe dynastie égyptienne | Twenty-ninth dynasty of Egypt |
| XXVe dynastie égyptienne | Twenty-fifth dynasty of Egypt |
| XXVIe dynastie égyptienne | Twenty-sixth dynasty of Egypt |
| XXVIIe dynastie égyptienne | Achaemenid dynasty |
| XXVIIIe dynastie égyptienne | Twenty-eighth dynasty of Egypt |
| XXXe dynastie égyptienne | Thirtieth dynasty of Egypt |
| XXXHOLiC | XxxHolic |
| Xylem Tube | Xylem Tube EP |
| Xylocopinae | Xylocopinae |
| xylographie | xylography |
| Xylokastro | Xylokastro |
| xylologie | xylology |
| xylophage | xylophagous |
| xylophone | xylophone |
