Oino was a language spoken in Osa Nara. It is a language isolate, meaning that researchers cannot find any demonstrable genealogical (or “genetic”) relationship with other languages, one that has not been demonstrated to descend from an ancestor common with any other language.

Due to that fact and also due to the historic circumstances of Osa Nara being conquered by the Kareden in the end of 18th CSR, the knowledge of oino was lost, with no documented native speakers already by the middle of the 19th CSR. The amount of historic artifacts uncovered to this day is inefficient to reconstruct the vocabulary and grammar of the written oino.