The Collaborative International Dictionary of English v.0.48:

Elucidation \E*lu`ci*da"tion\, n. [Cf. F. ['e]lucidation.]
   A making clear; the act of elucidating or that which
   elucidates, as an explanation, an exposition, an
   illustration; as, one example may serve for further
   elucidation of the subject.
   [1913 Webster]

WordNet (r) 3.0 (2006):

elucidation
    n 1: an act of explaining that serves to clear up and cast light
         on
    2: an interpretation that removes obstacles to understanding;
       "the professor's clarification helped her to understand the
       textbook" [syn: clarification, elucidation,
       illumination]