either of a pair of timbers or metal shapes lying along the tops of the hounds or cheeks of a mast to support crosstrees or a top.
Origin of trestletree
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019
nautical either of a pair of fore-and-aft timbers fixed horizontally on opposite sides of a lower masthead to support an upper mast
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