Pirithoüs
(paɪˈrɪθəʊəs) n (Classical Myth & Legend) Greek myth a prince of the Lapiths, who accomplished many great deeds with his friend Theseus
Collins English Dictionary – Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014