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Old English eorl "brave man, warrior, leader, chief" (contrasted with ceorl "churl"), from Proto-Germanic *erlo-z, of uncertain origin.
In Anglo-Saxon poetry, "a warrior, a brave man;" in later Old English, "nobleman," especially a Danish under-king (equivalent of cognate Old Norse jarl), then one of the viceroys under the Danish dynasty in England. After 1066 adopted as the equivalent of Latin comes (see count (n.)).