Rey

Spanish and southern French (Occitan): from Spanish and Old French rey ‘king’ (from Latin rex, genitive regis), which could have been applied any of in numerous ways: it may have denoted someone in the service of a king; it may have been from the title of someone in a brotherhood; or a nickname for someone who behaved in a regal fashion or who had earned the title in some contest of skill or by presiding over festivities.