Eclaircise

from The Collaborative International Dictionary of English v.0.48

Eclaircise \E*clair"cise\, v. t. [F. ['e]claircir; pref. es- (L.
   ex) + clair clear, L. clarus.]
   To make clear; to clear up what is obscure or not understood;
   to explain.
   [1913 Webster]