| Part of speech | common noun |
|---|---|
| Plural | dukes |
| Afrikaans | hertog |
|---|---|
| Catalan | duc |
| Czech | kníže; vévoda |
| Dutch | hertog |
| Esperanto | duko |
| Faeroese | hertugi |
| German | Herzog |
| Icelandic | hertogi |
| Italian | duca |
| Low German | hartog |
| Luxemburgish | Herzog |
| Papiamento | duke |
| Portuguese | duque |
| Saterland Frisian | Härtsoch |
| Spanish | duque |
| Swedish | hertig |
| Turkish | duka; dük |
| Welsh | dug |
| West Frisian | hartoch |