Where does “pers” come from?

pers (French) comes from Late Latin persus, from Latin Persicus, from Ancient Greek περσικός, from Ancient Greek Πέρσης, from Old Persian 𐎱𐎠𐎼𐎿, from Proto-Iranian párcuš, from Proto-Indo-Iranian párćuš, from Proto-Indo-European pérḱus — chest; rib.

pers (French): blue-green