| O'chi'chi' Language
|
| O'du Language
|
| O'odham language
|
| Obanliku Language
|
| Obispeño Language
|
| Oblo Language
|
| Obokuitai Language
|
| Obolo Language
|
| Obulom Language
|
| Ocaina Language
|
| Occitan (post 1500) Language
|
| Od Language
|
| Odiai Language
|
| Odoodee Language
|
| Odual Language
|
| Odut Language
|
| Ofayé Language
|
| Official Aramaic (700-300 BCE) Language
|
| Ofo Language
|
| Ogan Language
|
| Ogbah Language
|
| Ogbia Language
|
| Ogbogolo Language
|
| Ogbronuagum Language
|
| Ogea Language
|
| Ohlone, Northern Language
|
| Ohlone, Southern Language
|
| Oirata Language
|
| Ojibwa Language
|
| Ojibwa, Central Language
|
| Ojibwa, Eastern Language
|
| Ojibwa, Northwestern Language
|
| Ojibwa, Severn Language
|
| Ojibwa, Western Language
|
| Okanagan Language
|
| Oki-No-Erabu Language
|
| Okiek Language
|
| Okinawan, Central Language
|
| Oko-Eni-Osayen Language
|
| Oko-Juwoi Language
|
| Okobo Language
|
| Okodia Language
|
| Okolod Language
|
| Okpamheri Language
|
| Okpe Language
|
| Oksapmin Language
|
| Oku Language
|
| Old Aramaic (up to 700 BCE) Language
|
| Old Avar Language
|
| Old Breton Language
|
| Old Burmese Language
|
| Old Chinese Language
|
| Old Cornish Language
|
| Old Dutch Language
|
| Old French (842-ca. 1400) Language
|
| Old Frisian Language
|
| Old Georgian Language
|
| Old High German (ca. 750-1050) Language
|
| Old Hittite Language
|
| Old Hungarian Language
|
| Old Irish (to 900) Language
|
| Old Japanese Language
|
| Old Kentish Sign Language
|
| Old Korean (3rd-9th cent.) Language
|
| Old Manipuri Language
|
| Old Marathi Language
|
| Old Mon Language
|
| Old Nubian Language
|
| Old Ossetic Language
|
| Old Persian (ca. 600-400 B.C.) Language
|
| Old Provençal (to 1500) Language
|
| Old Russian Language
|
| Old Saxon Language
|
| Old Spanish language
|
| Old Tamil Language
|
| Old Tibetan Language
|
| Old Turkish Language
|
| Old Uighur Language
|
| Old Welsh Language
|
| Olekha Language
|
| Olo Language
|
| Oloma Language
|
| Olrat Language
|
| Olu'bo Language
|
| Olulumo-Ikom Language
|
| Omagua Language
|
| Omaha-Ponca Language
|
| Omati Language
|
| Ombamba Language
|
| Ombo Language
|
| Omejes Language
|
| Omi Language
|
| Omok Language
|
| Omotik Language
|
| Omurano language
|
| Ona Language
|
| One, Molmo Language
|
| One, Northern Language
|
| One, Southern Language
|
| Oneida Language
|
| Ong Language
|
| Onin Based Pidgin Language
|
| Onin Language
|
| Onjob Language
|
| Ono Language
|
| Onobasulu Language
|
| Onondaga Language
|
| Ontenu Language
|
| Ontong Java Language
|
| Oorlams Language
|
| Opao Language
|
| Opata Language
|
| Opuuo Language
|
| Orang Kanaq Language
|
| Orang Seletar Language
|
| Orejón Language
|
| Oring Language
|
| Oriya Language
|
| Oriya, Adivasi Language
|
| Orma Language
|
| Ormu Language
|
| Ormuri Language
|
| Oro Language
|
| Oro Win Language
|
| Oroch Language
|
| Oroha Language
|
| Orok Language
|
| Orokaiva Language
|
| Oroko Language
|
| Orokolo Language
|
| Oromo, Borana-Arsi-Guji Language
|
| Oromo, Eastern Language
|
| Oromo, West Central Language
|
| Oroqen Language
|
| Orowe Language
|
| Oruma Language
|
| Orya Language
|
| Osage Language
|
| Osatu Language
|
| Osetin Language
|
| Osing Language
|
| Ososo Language
|
| Otank Language
|
| Oti Language
|
| Otomi, Eastern Highland Language
|
| Otomi, Estado de México Language
|
| Otomi, Ixtenco Language
|
| Otomi, Mezquital Language
|
| Otomi, Querétaro Language
|
| Otomi, Temoaya Language
|
| Otomi, Tenango Language
|
| Otomi, Texcatepec Language
|
| Otomi, Tilapa Language
|
| Otoro Language
|
| Ottawa Language
|
| Ottoman Turkish (1500-1928) Language
|
| Otuho Language
|
| Otuke Language
|
| Ouma Language
|
| Oune Language
|
| Owa Language
|
| Owenia Language
|
| Owiniga Language
|
| Oy Language
|
| Oya'oya Language
|
| Oyda Language
|