1
Esperanto
The most successful constructed international auxiliary language — created by L. L. Zamenhof in 1887 to serve as a politically neutral second language for all.
You're looking for 9-letter languages containing O — here are 4 matches, each linked to a full profile.
List of 9-letter Languages that contain O
2
Mongolian
A Mongolic language and the official tongue of Mongolia — about 5.7 million speakers across Mongolia, Inner Mongolia (China), and Russia.
3
Norwegian
A North Germanic language with two written standards (Bokmål and Nynorsk) — official in Norway, mutually intelligible with Swedish and Danish.
4
Wampanoag
An Eastern Algonquian language of the Wampanoag people of present-day Massachusetts — extinct as a first language in the 19th century, now being revived.
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