Where does “keskiketterä” come from?

keskiketterä (Finnish) comes from Finnish Keski-, from Proto-Finnic keski, from Proto-Finno-Permic keske.

Ancestry of “keskiketterä”, step by step

StepLanguageWordMeaning
1FinnishKeski-middle, central; average, mid-, medium
2Proto-Finnickeskimiddle, center
3Proto-Finno-Permickeske—
Every word from Proto-Finno-Permic keske →Every word from Finnish Keski- →Every word from Proto-Finnic keski →