The Collaborative International Dictionary of English v.0.48:

Nurl \Nurl\ (n[^u]rl), v. t. [imp. & p. p. Nurled (n[^u]rld);
   p. pr. & vb. n. Nurling.] [Cf. Knurl.]
   To cut with reeding or fluting on the edge of, as coins, the
   heads of screws, etc.; to knurl.
   [1913 Webster]