noun.
A saw that is reinforced by a metal band along its back edge.
The Century Dictionary and Cyclopedia
noun.
A saw the web of which is stiffened by a metallic back of greater substance. Such saws have specific names according to their use, as tenon-saw, dovetail-saw, carcass-saw, etc.
the GNU version of the Collaborative International Dictionary of English
noun.
A saw (as a tenon saw) whose blade is stiffened by an added metallic back.