The Collaborative International Dictionary of English v.0.48:

Internode \In"ter*node`\, n. [L. internodium; inter between +
   nodus knot.]
   [1913 Webster]
   1. (Bot.) The space between two nodes or points of the stem
      from which the leaves properly arise. --H. Spenser.
      [1913 Webster]

   2. (Anat.) A part between two joints; a segment;
      specifically, one of the phalanges.
      [1913 Webster]

WordNet (r) 3.0 (2006):

internode
    n 1: a segment of a stem between two nodes