Where does “kääpäsieni” come from?

kääpäsieni (Finnish) comes from Finnish sieni, from Proto-Finnic seeni, from Proto-Uralic śänä — bracket fungus.

Ancestry of “kääpäsieni”, step by step

kääpäsieni traces back through two separate lines of ancestry.

via Finnish sieni

StepLanguageWordMeaning
1Finnishsienifungus; mushroom; sponge, bath sponge; shorter...
2Proto-Finnicseenifungus; mushroom
3Proto-Uralicśänäbracket fungus

via Finnish kääpä

StepLanguageWordMeaning
1Finnishkääpäpolypore, bracket fungus, shelf fungus; conk
Every word from Proto-Uralic śänäEvery word from Proto-Finnic seeniEvery word from Finnish sieni