Balios

In Greek mythology, Balius ("Dappled") and Xanthus ("Blonde") were two immortal horses, the offspring of the harpy Podarge and the West wind, Zephyros (lat. Zephyrus); following another tradition, their father was Zeus.Note: Balius and Xanthus are the Latin forms of the Greek names Balios and Xanthos.
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[Greek heroic] The immortal horse of Achilles, a gift from Poseidon to Achilles' father Peleus.

[Greek] One of two immortal horses that Poseidon gave to Peleus as a wedding present. See: Xanthus.