A supreme chief or leader in ancient Britain.
[Middle Welsh penndragon, pendragon (probably literally "chief of chieftains") : penn, head, chief (akin to Irish ceann; both Middle Welsh and Irish from Proto-Celtic *kwennom, of unknown origin) + dragon, plural of dreic, dragon, military leader, chieftain (from Latin dracō, dracōn-, large serpent, dragon, Roman cavalry standard consisting of a windsock in the form of a dragon; see DRAGON).]
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