The Collaborative International Dictionary of English v.0.48:

Divergence \Di*ver"gence\, Divergency \Di*ver"gen*cy\, n. [Cf.
   F. divergence.]
   1. A receding from each other in moving from a common center;
      the state of being divergent; as, an angle is made by the
      divergence of straight lines.
      [1913 Webster]

            Rays come to the eye in a state of divergency.
                                                  --??????.
      [1913 Webster]

   2. Disagreement; difference.
      [1913 Webster]

            Related with some divergence by other writers. --Sir
                                                  G. C. Lewis.
      [1913 Webster]

WordNet (r) 3.0 (2006):

divergency
    n 1: an infinite series that has no limit [syn: divergence,
         divergency] [ant: convergence, convergency]
    2: the act of moving away in different direction from a common
       point; "an angle is formed by the divergence of two straight
       lines" [syn: divergence, divergency]