The Collaborative International Dictionary of English v.0.48:

Neuron \Neu"ron\, n.; pl. Neura. [NL., from Gr. ney^ron
   nerve.] (Anat.)
   1. The brain and spinal cord; the cerebro-spinal axis;
      myelencephalon. [obsolete] --B. G. Wilder.
      [1913 Webster]

   2. (Cell Biology) The characteristic specialized cell that is
      part of the nervous system, serving to conduct electrical
      impulses to and from the brain, and also between other
      parts of the body, and composed of a main cell body, the
      axon, with a varying number of processes of varying
      length, the dendrites; a nerve cell. The movement and
      behavior of higher animals depends on the signals
      tranmsitted by such nerve cells.
      [PJC]