"sea eagle," from Old English earn "eagle," from Proto-Germanic *aron-, *arnuz "eagle" (cognates: Old High German arn, German Aar, Middle Dutch arent, Old Norse örn, Gothic ara "eagle"), from PIE root *or- "great bird" (cognates: Greek ornis "bird," Old Church Slavonic orilu, Lithuanian erelis, Welsh eryr "eagle"). The Germanic word also survives in the first element of names such as Arnold and Arthur.