wishbone boom

noun

a boom on a sailboard having two arms that are joined at the mast and at the foot of the sail. The windsurfer holds onto it for support and to steer the sailboard

Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012