zorbonaut (?z??b??n??t) n (Extreme Sports) jocular a person who engages in the activity of zorbing[C20: from zorb(ing) + -naut]Collins English Dictionary ? Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014