Where does “-au” come from?

-au (Finnish) comes from Finnish -ao, from Proto-Finnic -ado, from Proto-Finnic -o, from Proto-Uralic -w.

Ancestry of “-au”, step by step

StepLanguageWordMeaning
1Finnish-ao—
2Proto-Finnic-ado—
3Proto-Finnic-oForms action/result nouns from verbs
4Proto-Uralic-w—

Words derived from “-au”

Every word from Proto-Uralic -w →Every word from Proto-Finnic -o →Every word from Finnish -ao →