A slit, notch, or cut made by an ax, saw, blade, or cutting torch, or the width of such a space made by such tools. Sometimes, the first mark of this sort which establishes where the tool could go from there. Historically a kerf was made in wood, but today, a slit, notch, or cut made in metal, plastic, or another comparable material might also be called a kerf. A series of (usually parallel) kerfs are sometimes placed in a material in order to bend it, relieve stress, or prevent distortion. Kerfs have been used in bookbinding. This word, sometimes (although rarely) spelled "cerf," came to us from the same prehistoric word from which now have the word "carve."Also see corrugate, crosscut saw, circular saw, declivity, hacksaw, miter, mortise, pleat, and ripsaw.