Source : Webster's Revised Unabridged Dictionary (1913)

Od \Od\, n. [G., fr. Gr. ? passage.] (Physics)
   An alleged force or natural power, supposed, by Reichenbach
   and others, to produce the phenomena of mesmerism, and to be
   developed by various agencies, as by magnets, heat, light,
   chemical or vital action, etc.; -- called also {odyle} or the
   {odylic force}. [Archaic]

         That od force of German Reichenbach Which still, from
         female finger tips, burnt blue.          --Mrs.
                                                  Browning.