Where does “мечь” come from?

мечь (Old East Slavic) comes from Proto-Slavic mečь, from Proto-Germanic mēkijaz — sword.

Ancestry of “мечь”, step by step

StepLanguageWordMeaning
1Proto-SlavicmečьAlternative form of *mь̀čь
2Proto-Germanicmēkijazsword
Every word from Proto-Germanic mēkijaz →Every word from Proto-Slavic mečь →