Where does “pentécontarque” come from?

pentécontarque (French) comes from Latin pentēcontarchus, from Ancient Greek πεντηκόνταρχος, from Ancient Greek πεντήκοντα, from Proto-Indo-European penkʷēḱomth₂, from Proto-Indo-European *pénkʷedḱomt.

Ancestry of “pentécontarque”, step by step

StepLanguageWordMeaning
1Latinpentēcontarchuspentecontarch
2Ancient Greekπεντηκόνταρχοςpentecontarch
3Ancient Greekπεντήκονταfifty
4Proto-Indo-Europeanpenkʷēḱomth₂—
5Proto-Indo-European*pénkʷedḱomt—
Every word from Proto-Indo-European *pénkʷedḱomt →Every word from Proto-Indo-European penkʷēḱomth₂ →Every word from Ancient Greek πεντήκοντα →