The Collaborative International Dictionary of English v.0.48:

slitting \slit"ting\ (sl[i^]t"t[i^]ng),
   a. & n. from slit.
   [1913 Webster]

   slitting file. See Illust.
   (i) of sile.

   slitting mill.
   (a) A mill where iron bars or plates are slit into narrow
       strips, as nail rods, and the like.
   (b) A machine used by lapidaries for slicing stones, usually
       by means of a revolving disk, called a slicer, supplied
       with diamond powder.

   slitting roller, one of a pair of rollers furnished with
      ribs entering between similar ribs in the other roller,
      and cutting like shears, -- used in slitting metals.
      [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Slit \Slit\, v. t. [imp. & p. p. Slit or Slitted; p. pr. &
   vb. n. Slitting.] [OE. slitten, fr. sliten, AS. st[imac]tan
   to tear; akin to D. slijten to wear out, G. schleissen to
   slit, split, OHG. sl[imac]zan to split, tear, wear out, Icel.
   st[imac]ta to break, tear, wear out, Sw. slita, Dan. slide.
   Cf. Eclat, Slate, n., Slice.]
   1. To cut lengthwise; to cut into long pieces or strips; as,
      to slit iron bars into nail rods; to slit leather into
      straps.
      [1913 Webster]

   2. To cut or make a long fissure in or upon; as, to slit the
      ear or the nose.
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   3. To cut; to sever; to divide. [Obs.]
      [1913 Webster]

            And slits the thin-spun life.         --Milton.
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