| olaglighet | illegality |
| Olanzapin | Olanzapine |
| Olaus Magnus | Olaus Magnus |
| Olaus Petri | Olaus Petri |
| Olav | Olav |
| Olav I Tryggvason | Olaf I of Norway |
| Olav III Kyrre | Olaf III of Norway |
| Olav Magnusson | Olaf Magnusson of Norway |
| Olav V av Norge | Olav V of Norway |
| Olbia | Olbia |
| Olbia-Tempio | Province of Olbia-Tempio |
| Old Boy - hämnden | Oldboy |
| Old Course | Old Course at St Andrews |
| Old Faithful | Old Faithful Geyser |
| Old Firm | Old Firm |
| Old Trafford | Old Trafford |
| Oldenburg | Oldenburg |
| Oldenburgare | Oldenburg |
| Oldfield Thomas | Oldfield Thomas |
| Oldham | Oldham |
| Oldham County | Oldham County |
| Oldsmobile | Oldsmobile |
| Olduvai | Olduvai Gorge |
| Ole Bull | Ole Bull |
| Ole Einar Bjørndalen | Ole Einar Bjørndalen |
| Ole Gunnar Solskjær | Ole Gunnar Solskjær |
| Ole Rømer | Ole Rømer |
| Ole von Beust | Ole von Beust |
| Ole Worm | Ole Worm |
| ole, dole, doff | eeny, meeny, miny, moe |
| oleander | oleander |
| Oleanderväxter | Apocynaceae |
| OLED | Organic light-emitting diode |
| Oleg | Oleg |
| Oleg av Kiev | Oleg of Novgorod |
| Oleg Blochin | Oleg Blokhin |
| Oleg Cassini | Oleg Cassini |
| Oleg Gordievskij | Oleg Gordievsky |
| Oleg Jankovskij | Oleg Yankovsky |
| Oleg Kotov | Oleg Kotov |
| Oleg Lundstrem | Oleg Lundstrem |
| Oleg Salenko | Oleg Salenko |
| Oleguer Presas | Oleguer Presas |
| Oleksij Lukasjevitj | Olexiy Lukashevych |
| Olena Zubrilova | Olena Zubrilova |
| Olesia Krasnomovets | Olesya Krasnomovets |
| Olga | Olga |
| Olga av Kiev | Olga of Kiev |
| Olga Danilova | Olga Danilova |
| Olga Korbut | Olga Korbut |
| Olga Kotljarova | Olga Kotlyarova |
| Olga Kuzenkova | Olga Kuzenkova |
| Olga Morozova | Olga Morozova |
| Olga Nikolajevna Romanova | Olga Nikolaevna of Russia |
| Olga Preobrazjenskaja | Olga Preobrajenska |
| Olga Pyljova | Olga Pyleva |
| Olga Rjabinkina | Olga Ryabinkina |
| Olga Savjalova | Olga Zavyalova |
| Olga Zajtseva | Olga Zaytseva |
| Olha Kobyljanska | Olha Kobylyanska |
| Olidans kraftverk | Olidan Power Station |
| olidlig | intolerance |
| Olifant | Olifant |
| oligarki | oligarchy |
| Oligarkins järnlag | Iron law of oligarchy |
| oligarkisk | oligarchic |
| Oligocen | Oligocene |
| oligopol | oligopoly |
| olik | diverse |
| olika | diverse |
| olika mål | conflict of aims |
| olikartad | distinct |
| olikhet | divergence |
| olikheter | dissimilarities |
| oliksidig | unequal-sided |
| oliktänkande | dissenter |
| Olimpia Asunción | Olimpia Asunción |
| Olimpiada Ivanova | Olimpiada Ivanova |
| Olinda | Olinda |
| oliv | olive |
| Olivberget | Mount of Olives |
| Oliveira da Figueira | Minor characters in The Adventures of Tintin |
| Oliver | Oliver |
| Oliver Bierhoff | Oliver Bierhoff |
| Oliver Cromwell | Oliver Cromwell |
| Oliver Dragojević | Oliver Dragojević |
| Oliver Hardy | Oliver Hardy |
| Oliver Hazard Perryklassen | Oliver Hazard Perry class frigate |
| Oliver Heaviside | Oliver Heaviside |
| Oliver Hirschbiegel | Oliver Hirschbiegel |
| Oliver Kahn | Oliver Kahn |
| Oliver McCall | Oliver McCall |
| Oliver Neuville | Oliver Neuville |
| Oliver Norvelle Hardy | Oliver Norvelle Hardy |
| Oliver Riedel | Oliver Riedel |
| Oliver Sacks | Oliver Sacks |
| Oliver Smithies | Oliver Smithies |
| Oliver Stone | Oliver Stone |
| Oliver Tambo | Oliver Tambo |
| Oliver Twist | Oliver Twist |
| Olivgrön | Olive |
| olivgrönt | olive |
| Olivia | Olivia |
| Olivia de Berardinis | Olivia De Berardinis |
| Olivia de Havilland | Olivia de Havilland |
| Olivia Lewis | Olivia Lewis |
| Olivia Newton-John | Olivia Newton-John |
| Olivier Besancenot | Olivier Besancenot |
| Olivier Grouillard | Olivier Grouillard |
| Olivier Messiaen | Olivier Messiaen |
| Olivier Panis | Olivier Panis |
| Olivin | Olivine |
| olivolja | olive oil |
| olivoljerester | olive oil mill wastewater |
