bowsaw

A saw held in one hand and consisting of a tubular metal frame largely in the shape of a bow, the detachable blade representing the bowstring. The blade is fixed at the two ends of the bow then tensioned by levering the handle against the frame. Bowsaws are used for crosscutting and have two kinds of blades

This definition is abridged from A – Z of tree terms: A companion to British arboriculture.
Read the preface. Order the book.