| Otolithes ruber | Otoman | Otomano |
| Otomanong Imperyo | Otomen | Oton |
| Oton, Iloilo | Otopsia | Otopsiya |
| Otopsya | Otor | Otoyo, Kōchi |
| Otradnoye, Kirovsky District, Leningrad Oblast | Otradny, Samara Oblast | Otranto |
| Otrhánky | Otricoli | Ots |
| Otsi, Kōchi | Otso-Otso Pamela-Mela-Wan | Otsu, Shiga |
| Otsu, Syiga | Otsuki, Kōchi | Otsuki, Yamanashi |
| Otsuki, Yamanasyi | Ott Tänak | Ottana |
| Ottati | Ottaviano | Ottaviano (Papa) |
| Ottawa | Otter | Ottiglio |
| Otto Bathurst | Otto Bismarck | Otto Eduard Leopold ng Bismarck |
| Otto Eduard Leopold von Bismarck | Otto Eduard ng Bismarck | Otto Heinrich Warburg |
| Otto Leopold ng Bismarck | Otto Neumann | Otto Neumann Sverdrup |
| Otto ng Bismarck | Otto Sverdrup | Otto von Bismarck |
| Otto von Gericke | Otto von Guericke | Otto Wilhelm Thomé |
| Otto Wilhelm Thome | Ottobiano | Ottoman |
| Ottoman Empire | Ottoman na Imperyo | Ottoman State |
| Ottomano | Ottomanong Imperyo | Ottone, Emilia-Romaña |
| Ottone, Emilia-Romagna | Otus mindorensis | Ouagadougou |
| Oud | Oude | Oudh |
| Oule | Oulx | Oum Hadjer |
| Oupis | Our Beloved Revolutionary Sweetheart | Our Father |
| Our Lady of Assumption College | Our Lady of Atonement Cathedral | Our Lady of Death |
| Our Lady of Fatima University | Our Lady of Guadalupe | Our Lady of Guadalupe Colleges |
| Our Lady of Lourdes College | Our Lady of Lourdes Technological College | Our Lady of Peñafrancia |
| Our Lady of Perpetual Succor College | Our Lady of Salambao | Our Lady of Salambaw |
| Our Lady of Sorrows | Our Lady of Succour | Our Lady of the Holy Rosary |
| Our Lady of the Most Holy Rosary | Our Lady of the Pillar College | Our Mother of Perpetual Help |
| Our Mother of Succour | Ouran High School Host Club | Ourano |
| Ouranos | Ouranus | Ourikel |
| Ourista | Ouro Preto | Ouroboros |
| Out | Out of the Races and Onto the Tracks | Out of Time |
| Out! | Outer space | Outer space exploration |
| Outer-space | Outerspace | Outismo |
| Outlaw | Outrageous and Courageous | Outreach |
| Outriaz | Outrigger | Outrigging |
| Outs | Ouwrista | Ova |
| OVA | Ovada | Oval |
| Oval (estadyo) | Ovarian follicle | Ovary |
| Ovejas (Sucre) | Over the Rainbow | Overgrazing |
| Overland Park, Kansas | Overpass | Overpass (estilo ng titik) |
| Overseas Filipino | Overseas Filipinos | Overseas Workers Welfare Administration |
| Overweight | Overweight child | Overweight children |
| Ovibos moschatus | Ovid | Ovidio |
| Ovidius | Oviduct | Oviducts |
| Oviglio | Ovilla Technical College | Ovindoli |
| Ovis orientalis | Ovodda | Ovulación |
| Ovulacion | Ovulate | Ovulation |
| Ovum | Owani, Aomori | Owariasahi |
| Owariasahi, Aichi | Owariasahi, Aitsi | Owase, Mie |
| Owe My Love | Owen Lovejoy | Owk |
| Owk (lungsod) | Owl | Owl City |
| Owrikel | Owrista | Owt |
| Owtismo | Owts | Owusu Kizito |
| Ox | Ox (zodiac) | Ox-like |
| Oxalis triangularis | Oxen | Oxford English Dictionary |
| Oxford–AstraZeneca | Oxfordian Colleges | Oxfordianong Dalubhasaan |
| Oxfordianong Kolehiyo | Oxlike | Oxnard, California |
| Oxter | Oxycoccos | Oxygen |
| Oxygen atom | Oxygeno | Oxyrhynchus Papyri |
| Oxyura vittata | Oyabe, Toyama | Oyace |
| Oyama, Shizuoka | Oyama, Tochigi | Oyama, Totsigi |
| Oyamazaki, Kyoto | Oyayi | Oynmenta |
| Oyntment | Oyntmente | Oyntmento |
| Oyo Sotto | Oyodo, Nara | Oyonnax |
| Oyster | Oyster Island | Ozamis City |
| Ozamiz | Ozamiz City | Ozan, Ain |
| Ozegna | Ozherelye | Ozias |
| Ozieri | Ozone | Ozone (singaw) |
| Ozone depletion | Ozone layer | Ozymandias |
| Ozyorsk, Chelyabinsk Oblast | Ozyorsk, Kaliningrad Oblast | Ozyory |
| Ozzano dell'Emilia | Ozzano Monferrato | Ozzero |
| Ӱ | Հայաստան | Հայաստանի Հանրապետություն |
| P | P & G | P anisum |
| P antarcticum | P B S Pinchback | P Blaud |
| P Blaud de Beaucaire | P Blaud ng Beaucaire | P Blaud of Beaucaire |
| P cinereus | P concolor | P dactylifera |
| P E | P electra | P gangetica |
| P gangetica gangetica | P gangetica minor | P haliaetus |
| P indicus | P montanus | P N P |
| P onca | P pardus | P pelagicus |
| P peltatum | P pubis | P saltatrix |
| P sanguinolentus | P sanguinotentus | P serrulata |
| P stirtoni | P tigris tigris | P&G |
| P&g | P'yŏngyang | P-Pop |
| P. anisum | P. antarcticum | P. B. S. Pinchback |
| P. Blaud | P. Blaud de Beaucaire | P. Blaud ng Beaucaire |
| P. Blaud of Beaucaire | P. cinereus | P. concolor |
| P. dactylifera | P. E. | P. E. Winfield |
| P. electra | P. G. Wodehouse | P. gangetica |
| P. gangetica gangetica | P. gangetica minor | P. Gannavaram |
| P. haliaetus | P. I. A. | P. indicus |
| P. K. van der Byl | P. Kalimuthu | P. L. M. |
| P. M. Pimsleur | P. montanus | P. N. P. |
| P. onca | P. pardus | P. pelagicus |
| P. peltatum | P. Pimsleur | P. pubis |
| P. R. Thippeswamy | P. saltatrix | P. sanguinolentus |
| P. sanguinotentus | P. sativa | P. serrulata |
| P. stirtoni | P. T. Barnum | P. tigris tigris |
