kerf

kerf (KÛRF) - n., the groove or notch made by a cutting tool, such as by (especially) a saw or an axe; the width of a groove made by a cutting tool; (mining) a deep cut used to undermine a portion of a coal or mineral seam. v., to make a kerf or kerfs (in wood, in a coal seam, et cet.).


The kerf (second sense) of a saw is wider than the width of the blade because the teeth lean out on either side -- which is important, or otherwise the blade would get caught (or bind) in the kerf (first sense). The difference between the blade width and the kerf (second sense) is the set. All of this goes back to Old English cyrf, a cutting, related to ceorfan, to carve.

---L.