(g hard). A human monster with three bodies and three heads, whose oxen ate human flesh, and were guarded by a two-headed dog. Hercules slew both Geryon and the dog. This fable means simply that Geryon reigned over three kingdoms, and was defended by an ally, who was at the head of two tribes.
Source: Dictionary of Phrase and Fable, E. Cobham Brewer, 1894
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