| O 4 | O 5 | O 6 |
| O 7 | O 8 | O 9 |
| O 9-klasse | O alte Burschenherrlichkeit | O Amor Natural |
| O Amor Natural (boek) | O Amor Natural (film) | O arise all you sons of this land |
| O Arise, All You Sons | O Baixo Miño | O Baixo Mino |
| O Barco de Valdeorras | O Bobo | O Bolo |
| O bon vin, où as-tu crû | O bon vin, ou as-tu cru | O brother where art thou |
| O brother where art thou? | O brother, where art thou | O Brother, Where Art Thou? |
| O Canada | O Canada! | O Carballiño |
| O Carballino | O Condado | O Corgo |
| O Dame get up and bake your pies | O denneboom | O dennenboom |
| O Deza | O die 3 | O Dragao da Maldade contra o Santo Guerreiro |
| O Dragao da Maldade Contra o Santo Guerreiro | O Dragão da Maldade contra o Santo Guerreiro | O Dragão da Maldade Contra o Santo Guerreiro |
| O du, der du die Liebe bist | O Earth, O Stars | O Ejebjaerg |
| O esca viatorum | O Eume | O Ewigkeit, du Donnerwort |
| O filii et filiae | O fons Bandusiae | O Fortuna |
| O Globo | O Gran Camiño | O Grove |
| O Haupt voll Blut und Wunden | O heil'ge nacht | O Heraldo |
| O Holy Night | O hoofd vol bloed en wonden | O II |
| O III | O Incio | O intemerata |
| O Irixo | O IV | O julissi |
| O Kersnacht schooner dan de daegen | O Kerstnacht, schoner dan de dagen | O Kerstnacht, schooner dan de daegen |
| O Lam | O le Ao o le Malo | O Long Vi |
| O Lord God of hosts | O Lucky Man! | O mie |
| O mijn God-deeltje | O mijn papa | O mio babbino caro |
| O Morrazo | O morte | O Mundo |
| O o Den Haag | O O Den Haag | O Ornitólogo |
| O ornitólogo | O Pagador de Promessas | O papagaio do moleque |
| O Paramo | O Páramo | O Pereiro de Aguiar |
| O Pino | O plus S | O Porriño |
| O Porrino | O Praise God in his Holiness | O que arde |
| O reinste der schepselen | O Ribeiro | O RLY |
| O rly | O RLY? | O Rosal |
| O sabor das margaridas | O Salnés | O Salnes |
| O Sar | O Saviñao | O Savinao |
| O Sensei | O sensei | O Sole Mio |
| O Sterre der Zee | O styago le romengo | O Superman |
| O Surdato 'Nnamurato | O Sweet Saint Martin's Land | O sweet Saint-Martin's Land |
| O tannenbaum | O telefone chora | O tempora! o mores! |
| O tempora, o mores | O tempora, o mores! | O Thiasos |
| O Thiassos | O V | O Valadouro |
| O Veux | O Vicedo | O Welt, ich muss dich lassen |
| O Yeah Aha Oh | O&g verpleegkundige | O&g-verpleegkundige |
| O&I | O&O | O&O (restaurant) |
| O&O Defrag | O' Valley | O'42 |
| O'68 | O'ahu | O'Amate |
| O'Brien | O'Brien (Texas) | O'Brien County |
| O'Brien County (Iowa) | O'Brien County, Iowa | O'Brien's Tower |
| O'Brien-klasse | O'Brienklasse | O'Briensbridge |
| O'Callaghans Mills | O'Carolan | O'Connell Bridge |
| O'Connell Street | O'Connor | O'connor |
| O'Cool | O'Day | O'Death |
| O'Donel Levy | O'Donnel's | O'Donnell |
| O'Donnell (metrostation) | O'Donnell (Texas) | O'Donoghue's |
| O'Donoghue's Pub | O'Fallon | O'Fallon (Illinois) |
| O'Fallon (Missouri) | O'G3NE | O'Hanlons Helden |
| O'Hara | O'hara | O'Hara Township |
| O'Hara Township (Pennsylvania) | O'Hara's Playboys | O'Hare International Airport |
| O'Higgins | O'Higgins (departement) | O'Higgins (gemeente) |
| O'Higginsmeer/San Martínmeer | O'Higginsmeer/San Martinmeer | O'Jays |
| O'jays | O'Kean | O'Kean (Arkansas) |
| O'Keefe | O'Keeffe | O'Kelly de Galway |
| O'Kellygambiet | O'Neil Longson | O'neil Longson |
| O'Neill | O'Neill (Nebraska) | O'Neill Spencer |
| O'o | O'O | O'obibi |
| O'odham | O'Reilly | O'reilly |
| O'Russei markt | O'Russeimarkt | O'Shaughnessy's kameleon |
| O'Shea Jackson | O'Shea Jackson jr. | O'Shea Jackson Jr. |
| O'Sheas Casino | O'Tacos | O'Toole |
| O'toole | O'u | O'zbekiston Respublikasining Davlat Madhiyasi |
| O'zbekiston Superligasi | O+S | O+S (band) |
| O, dat je doodgaat | O, die herfstdagen, die allerlaatste mooie herfstdagen | O, Holy Night |
| O, Kerstnacht, schoner dan de dagen | O, kom er eens kijken | O, mijn papa |
| O, o, Den Haag | O, O, Den Haag | O, reinste der schepselen |
| O, Sørland, du min moderjord | O, Sorland, du min moderjord | O, The Oprah Magazine |
| O,159 Transport (schip, 1928) | O,O-dimethyldithiofosforzuur | O,S-Dimethyl phosphorochloridothioate |
| O-1 | O-1 (Turkije) | O-11 |
| O-12 | O-14 | O-2 |
| O-2 (Turkije) | O-20 | O-20 (Turkije) |
| O-21 (Turkije) | O-21A (Turkije) | O-22 |
| O-22 (Turkije) | O-3 | O-3 (Turkije) |
| O-30 (Turkije) | O-31 (Turkije) | O-32 (Turkije) |
| O-33 (Turkije) | O-4 | O-4 (Turkije) |
| O-5 | O-5 (Turkije) | O-50 (Turkije) |
| O-51 (Turkije) | O-52 (Turkije) | O-53 (Turkije) |
| O-54 (Turkije) | O-6 (Turkije) | O-7 (Turkije) |
| O-aminofenol | O-anisidine | O-antifonen |
| O-antifoon | O-antigeen | O-Bahn |
| O-been | O-benen | O-chloorbenzaldehyde |
| O-chloorbenzylideenmalonitril | O-chloorbenzylideenmalonnitril | O-chloorfenol |
| O-chloranil | O-cresylglycidylether | O-cymeen |
| O-di-ethylbenzeen | O-diethylbenzeen | O-Dog |
| O-dog | O-ethyl-O-4-nitrofenylfenylthiofosfonaat | O-Game |
| O-gō | O-go | O-gon Kwon |
| O-Gon Kwon | O-goshi | O-H-Hemelvaart |
| O-I | O-klasse | O-League |
| O-nitrotolueen | O-notatie | O-pa-me |
| O-Ren Ishii | O-ring | O-Ringen |
| O-ringen ketting | O-ringenketting | O-sekoer |
| O-Shen | O-soto-gari | O-tolidine |
