Where does “omankielinen” come from?

omankielinen (Finnish) comes from Finnish kieli, from Proto-Finnic keeli, from Proto-Uralic käle — tongue; language.

Ancestry of “omankielinen”, step by step

omankielinen traces back through two separate lines of ancestry.

via Finnish kieli

StepLanguageWordMeaning
1Finnishkielitongue; language; string
2Proto-Finnickeelitongue; language
3Proto-Uralickäletongue; language

via Finnish oma

StepLanguageWordMeaning
1Finnishomaown; friendly
2Proto-Finnicomaown
Every word from Proto-Uralic käle →Every word from Proto-Finnic keeli →Every word from Finnish kieli →