porgy (n.)

name given in U.S. to various sea fishes, 1725, probably from porgo, pargo "sea bream" (1550s), from Spanish or Portuguese pargo, from Latin phagrum (nom. phager), from Greek phagros "sea bream," which Beekes says probably is identical with phagros, a Cretan word for "whetstone" (perhaps from a PIE root for "sharpening"), "because of the pointed shape of the body, or the sharp teeth."