| | objectifs du millénaire pour le développement |
| | observatoire |
| | Océan indien |
| | occupation des sols |
| | oceanic metaphors |
| | ocio |
| | Octavio Paz |
| | offerte touristique |
| | old center |
| | oligopole |
| | oligopoly |
| | omnivore paradox |
| | OMT |
| | ontología |
| | ontologie |
| | ontology |
| | opulence |
| | Oral culture |
| | Organisation de l’Unité africaine |
| | organisation internationale |
| | organisation spatiale |
| | organismes de promotion culturelle et linguistique |
| | organismo de promoción cultural y lingüística |
| | organización del trabajo |
| | organización espacial |
| | Organization of African Unity |
| | organization of labor |
| | organizations promoting cultural and linguistic diversity |
| | orientation générale |
| | original label |
| | ostentación |
| | ost:Multidisciplinary |
| | other |
| | otredad |
| | ouragan |
| | outdoor sport |
| | outermost regions |
| | outre-mer |
| | Outre-mer français |
| | overdevelopment and sustainable development |
| | oversea department |
| | overseas |
| | overseas region |
| | ownership |