In 
Greek mythology, 
Ixion was one of the 
Lapiths, and a son of 
Phlegyas.  
Pirithous was his son.  He married a daughter of 
Deioneus and, in order to avoid paying the bride-price, pushed him into a bed of coals.  For this, he was punished in 
Tartarus after his death by spending eternity on a flaming wheel.
He was sometimes thought of as an ancestor of the centaurs.  Hence, they were called Ixionidae.
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