Two pieces of oak secured to the topsides of a square-rigged sailing ship at the point where the curve of the bow began to straighten out for the run aft, one on each side of the ship. Normally they had a hole through them in the centre, but occasionally they were fitted with a sheave. The bowlines with which the main tacks were hauled down were led through the hole or sheave in the chesstrees to give the crew a clear haul. See also veer and haul, to.
Subjects: Maritime History.