Jagging

from The Collaborative International Dictionary of English v.0.48

Jag \Jag\, v. t. [imp. & p. p. {Jagged}; p. pr. & vb. n.
   {Jagging}.]
   To cut into notches or teeth like those of a saw; to notch.
   [Written also {jagg}.]
   [1913 Webster]

   {Jagging iron}, a wheel with a zigzag or jagged edge for
      cutting cakes or pastry into ornamental figures.
      [1913 Webster]