Pedro

Peter (leading Apostle in the New Testament); a male given name from Ancient Greek, equivalent to English Peter

“A Simón, al cual puso por nombre Pedro.” — And Simon he surnamed Peter; (KJV)

Inherited from Old Spanish Pedro, from Latin Petrus, from Ancient Greek Πέτρος (Pétros), from πέτρος (pétros, “stone, rock”), related to πέτρα (pétra) (compare piedra). The lack of diphthongization of the short stressed /ɛ/ in Latin to /je/, which would have yielded *Piedro, is irregular.