Where does “mittewoche” come from?

mittewoche (Middle High German) comes from Old High German mittawehha, from Ecclesiastical Latin media hebdomas.

Ancestry of “mittewoche”, step by step

Step	Language	Word	Meaning
1	Old High German	mittawehha	Wednesday
2	Ecclesiastical Latin	media hebdomas	—

mittewoche — Etymology, Origin & Word History | Etymology Explorer