| Part of speech | common noun |
|---|
| Czech | optimismus |
|---|---|
| Dutch | optimisme |
| English | optimism |
| Esperanto | optimismo |
| Faeroese | bjartskygni |
| French | optimisme |
| German | Optimismus |
| Italian | ottimismo |
| Papiamento | optimismo |
| Portuguese | otimismo |
| Saterland Frisian | Optimismus |
| Spanish | optimismo |
| Swedish | optimism |
| Welsh | optimistiaeth |