Source : Webster's Revised Unabridged Dictionary (1913)

Nodal \Nod"al\, a.
   Of the nature of, or relating to, a node; as, a nodal point.

   {Nodal line}, {Nodal point}, in a vibrating plate or cord,
      that line or point which remains at rest while the other
      parts of the body are in a state of vibration.

Source : Free On-Line Dictionary of Computing

NODAL
     
        Interpreted language implemented on Norsk Data's NORD-10
        computers.  Used by CERN and DESY high energy physics labs to
        control their accelerator hardware, PADAC and SEDAC.  Included
        trackball input, graphics.