| okra | quingombó |
| Oktoberfest | Oktoberfest |
| Okubo Toshimichi | Ōkubo Toshimichi |
| Okurigana | Okurigana |
| Ola | La ola |
| Olaberria | Olaberría |
| Olaf Ier de Norvège | Olaf I de Noruega |
| Olaf II de Norvège | Olaf II el Santo |
| Olaf III de Norvège | Olaf III de Noruega |
| Olaf IV de Norvège | Olaf Magnusson de Noruega |
| Olaf Stapledon | Olaf Stapledon |
| Olafur Ragnar Grimsson | Ólafur Ragnar Grímsson |
| OLAP | OLAP |
| Olaus Magnus | Olaus Magnus |
| Olav V de Norvège | Olaf V |
| Olavarría | Olavarría |
| Olbia | Olbia |
| Old Boy | Oldboy |
| Old Crow | Old Crow |
| Old Faithful | Old Faithful |
| Old school | Old school |
| Old Trafford | Old Trafford |
| Oldenbourg | Oldenburgo |
| Oldenburg | Oldenburgo |
| Oldham | Oldham |
| Oldham Athletic Association Football Club | Oldham Athletic |
| Oldman | Río Oldman |
| Oldowayen | Olduvayense |
| Oldrich Duras | Oldřich Duras |
| Oldřich Nejedlý | Oldřich Nejedlý |
| OLE | OLE |
| Ole Bull | Ole Bull |
| Ole Christensen Rømer | Ole Rømer |
| Ole Einar Bjørndalen | Ole Einar Bjorndalen |
| OLE for Process Control | OPC |
| Ole Gunnar Solskjær | Ole Gunnar Solskjær |
| Ole Worm | Olaus Wormius |
| Oleaceae | Oleaceae |
| Oleg Blokhine | Oleg Blojín |
| Oleg Cassini | Oleg Cassini |
| Oleg le Sage | Oleg |
| Oleg Lisogor | Oleg Lisogor |
| Oleg Menchikov | Oleg Menshikov |
| Oleg Penkovsky | Oleg Penkovsky |
| Oleg Salenko | Oleg Salenko |
| Oleg Serebrian | Oleg Serebrian |
| Oleg Vladimirovich Losev | Oleg Vladimirovich Losev |
| Oleguer Presas | Oleguer Presas |
| Oleksandr Shovkovskiy | Oleksandr Shovkovsky |
| Olenyok | Olenyok |
| olfactif | olfatorio |
| Olga | Olga de Kiev |
| Olga Alexandrovna | Olga Aleksándrovna Romanov |
| Olga Alexandrovna de Russie | Olga Aleksándrovna Romanov |
| Olga Bondarenko | Olga Bondarenko |
| Olga Bryzgina | Olga Bryzgina |
| Olga Constantinovna de Russie | Olga Konstantinovna Romanova |
| Olga de Russie | Olga Nikolayevna Romanova |
| Olga Korbut | Olga Korbut |
| Olga Nicolaevna de Russie | Olga Nikolayevna Romanova |
| Olga Nicolaïevna de Russie | Olga Nikolayevna Romanova |
| Olga Prekrasa | Olga de Kiev |
| Olga Preobrajenska | Olga Preobrajenska |
| Olgierd Zienkiewicz | Olgierd Zienkiewicz |
| Olgoï-Khorkhoï | Aka Allghoi Khorhoi |
| Olifant | Olifante |
| oligarchie | oligarquía |
| oligarchique | oligárquico |
| oligo-élément | microelemento |
| Oligochaeta | Oligochaeta |
| Oligocène | Oligoceno |
| Oligodendrocyte | Oligodendrocito |
| Oligonucléotide | Oligonucleótido |
| Oligophrénie | Oligofrenia |
| oligopole | oligopolio |
| Oligoryzomys | Oligoryzomys |
| Oligosaccharide | Oligosacárido |
| Olimpia Milan | Olimpia Milano |
| Olinda | Olinda |
| Oliniaceae | Oliniaceae |
| olisbos | consolador |
| Oliva de Besalù | Abad Oliba |
| olive | oliva |
| olive de duffel-coat | cabilla |
| Oliveira | Olea europaea |
| Oliveira da Figueira | Oliveira da Figueira |
| Oliveira de Azeméis | Oliveira de Azeméis |
| Oliveira de Frades | Oliveira de Frades |
| Oliveira do Hospital | Oliveira do Hospital |
| Olivenza | Olivenza |
| Oliver Bierhoff | Oliver Bierhoff |
| Oliver Cromwell | Oliver Cromwell |
| Oliver et Compagnie | Oliver y su pandilla |
| Oliver Heaviside | Oliver Heaviside |
| Oliver Hirschbiegel | Oliver Hirschbiegel |
| Oliver Kahn | Oliver Kahn |
| Oliver Lodge | Oliver Joseph Lodge |
| Oliver Neuville | Oliver Neuville |
| Oliver Riedel | Oliver Riedel |
| Oliver Sacks | Oliver Sacks |
| Oliver Smithies | Oliver Smithies |
| Oliver Stone | Oliver Stone |
| Oliver Tambo | Oliver Tambo |
| Oliver Twist | Oliver Twist |
| Oliver Wendell Holmes | Oliver Wendell Holmes |
| Olivia | Olivia |
| Olivia de Havilland | Olivia de Havilland |
| Olivia Lufkin | Olivia |
| Olivia Newton-John | Olivia Newton-John |
| Olivia Williams | Hotaru Tomoe |
| olivier | olivo |
| Olivier Besancenot | Olivier Besancenot |
| Olivier de la Marche | Olivier de la Marche |
| Olivier européen | Olea europaea |
| Olivier Grouillard | Olivier Grouillard |
| Olivier Messiaen | Olivier Messiaen |
| Olivier Panis | Olivier Panis |
| Olivier sauvage | Aeituno silvestre |
| Olivier van Noort | Oliverio van Noort |
| Olivine | Olivino |
| olivâtre | cetrino |
| Ollantaytambo | Ollantaytambo |
| Ollería | Ollería |
| Olli Rehn | Olli Rehn |
| Ollon | Ollon |
| Olmeta-di-Capocorso | Olmeta-di-Capocorso |
| Olmeta-di-Tuda | Olmeta-di-Tuda |
| Olmi-Cappella | Olmi-Cappella |
| Olmèques | Olmeca |
| Olof Bromelius | Olof Bromelius |
| Olof Celsius | Olof Celsius |
| Olof Celsius le jeune | Olof Celsius el joven |
| Olof de Suède | Olaf el Tesorero |
| Olof Palme | Olof Palme |
| Olof Peter Swartz | Peter Olof Swartz |
| Olof Rudbeck | Olaus Rudbeck |
| Olof Rudbeck le Jeune | Olof Rudbeck el Joven |
| Olokun | Olokun |
| Ololiuqui | Rivea corymbosa |
| Olomouc | Olomouc |
| Oloros | Óloro |
| Oloïde | Oloide |
| Olpe | Distrito de Olpe |
| Olsen Brothers | Olsen Brothers |
| Olsztyn | Olsztyn |
| Olt | Río Olt |
| Olten | Olten |
| Oltingen | Oltingen |
| Olténie | Oltenia |
| Oluf Ier de Danemark | Olav I de Dinamarca |
| Oluf III de Danemark | Olaf II de Dinamarca |
| Olusegun Obasanjo | Olusegun Obasanjo |
| Olve Eikemo | Olve Eikemo |
| Olybrius | Anicio Olibrio |
| Olympe | Olimpo |
| Olympe de Gouges | Olympe de Gouges |
| Olympe Maxime | Olympe Maxime |
| Olympia | Olympia |
| olympiade | olimpíada |
| Olympiades internationales de mathématiques | Olimpiada Internacional de Matemática |
| Olympiades Internationales de Physique | Olimpiada internacional de física |
| Olympiades internationales de sciences | Olimpiada internacional de ciencias |
| Olympiades populaires | Olimpiada Popular |
| Olympiakos | Olimpiakos CFP |
| Olympiakos Le Pirée | Olimpiakos CFP |
| Olympiakos Nicosie | Olympiakos Nicosia FC |
| Olympias | Olimpia de Epiro |
| Olympic Airways | Olympic Airlines |
| Olympie | Olimpia |
| Olympiodore | Olimpiodoro |
| Olympiodore le jeune | Olimpiodoro el Joven |
| Olympion | Templo de Zeus Olímpico |
| olympique | olímpico |
| Olympique de Marseille | Olympique de Marsella |
| Olympique lyonnais | Olympique Lyonnais |
| Olympiéion | Templo de Zeus Olímpico |
| Olympos | Olimpo |
| Olympus | Olympus |
| Olympus Mons | Monte Olimpo |
| Oléate | Aceite |
| Oléique | Oleico |
| oléoduc | tubería |
| Oléoduc Druzhba | Oleoducto Druzhba |
| oléographie | oleografía |
| OM | Ohmio |
| OMAC Project | Proyecto OMAC |
| Omaha | Omaha |
| Omaha Beach | Playa de Omaha |
| Omake | Omake |
| Oman | Omán |
| Omar | Umar ibn al-Jattab |
| Omar Ben Hafsun | Omar ibn Hafsún |
| Omar Bongo Ondimba | Omar Bongo |
| Omar Bradley | Omar Nelson Bradley |
| Omar el-Béchir | Omar Hasan Ahmad al-Bashir |
| Omar Epps | Omar Epps |
| Omar ibn al-Khattab | Umar ibn al-Jattab |
| Omar Karamé | Omar Karami |
| Omar Khayyam | Omar Jayyam |
| Omar Rodriguez-Lopez | Omar Rodríguez-López |
| Omar Sharif | Omar Sharif |
| Omar Sivori | Omar Sívori |
| Omar Torrijos | Omar Torrijos Herrera |
| Omaruru | Omaruru |
| Omayra Sanchez | Omayra Sánchez |
| ombelle | umbela |
| Ombellifères | Apiaceae |
| ombilic | ombligo |
