c.1300, from Old French hairon (12c.), earlier hairo (11c., Modern French héron), from Frankish *haigiro or some other Germanic source, from Proto-Germanic *hraigran (cognates: Old High German heigaro "heron," German Reiher, Dutch reiger, Old Norse hegri), from PIE *qriq-, perhaps imitative of its cry (compare Old Church Slavonic kriku "cry, scream," Lithuanian kryksti "to shriek"). Old English cognate hraga did not survive into Middle English.