| omöjlig | impossible |
| omöjlig att besvara | unanswerable |
| omöjlig att få bukt med | uncontrollable |
| omöjlig att minnas | past recall |
| omöjlig att skilja | indistinguishable |
| omöjlig att särskilja | indistinguishable |
| omöjlighet | impossibility |
| On Through the Night | On Through the Night |
| on-line | on-line |
| Onan | Onan |
| onanera | masturbate |
| onanerande | masturbating |
| onani | masturbation |
| onaturlig | unnatural |
| Once in a LIVEtime | Once in a LIVEtime |
| Once More With Feeling | Once More with Feeling |
| Once Upon a Time in America | Once Upon a Time in America |
| Once Upon a Time in Mexico | Once Upon a Time in Mexico |
| Oncifelis | Oncifelis |
| Oncorhynchus | Oncorhynchus |
| ond | mad |
| ond ande | fiend |
| ond cirkel | vicious circle |
| ond gärning | wrongdoing |
