Where does “valkoposkisaukko” come from?

valkoposkisaukko (Finnish) comes from Finnish poski, from Proto-Finnic poski, from Proto-Uralic poske — cheek.

Ancestry of “valkoposkisaukko”, step by step

valkoposkisaukko traces back through two separate lines of ancestry.

via Finnish poski

StepLanguageWordMeaning
1Finnishposkicheek
2Proto-Finnicposkicheek
3Proto-Uralicposkecheek

via Finnish saukko

StepLanguageWordMeaning
1FinnishsaukkoEuropean otter, "Lutra lutra"; otter; Old World...
2Proto-Finnicsagukkoi
3Proto-Finnicsagarvaotter
Every word from Proto-Uralic poske