Where does “firmō” come from?

firmō (Proto-Germanic) comes from Proto-Germanic firhu-, from Proto-Indo-European perkʷ- — oak.

Ancestry of “firmō”, step by step

StepLanguageWordMeaning
1Proto-Germanicfirhu-life force, body, being
2Proto-Indo-Europeanperkʷ-oak
Every word from Proto-Indo-European perkʷ- →Every word from Proto-Germanic firhu- →