The Toe, or Nab of the Bolt, which rises […] above the Straight on the Top of the Bolt: The Office of this Nab, is to receive the Bottom of the Bit of the Key, when in turning it about, it shoots the Bolt backward or forwards.
1677–1683, Joseph Moxon, “(please specify the page)”, in Mechanick Exercises, or The Doctrine of Handy-Works, […], volumes (please specify |volume=I or II), London: […] Joseph Moxon, published 1678–1683