The Collaborative International Dictionary of English v.0.48:

Itacism \I"ta*cism\, n. [Cf. F. itacisme. See Etacism, and cf.
   Iotacism.] (Greek Gram.)
   Pronunciation of [eta] (eta) as the modern Greeks pronounce
   it, that is, like e in the English word be. This was the
   pronunciation advocated by Reuchlin and his followers, in
   opposition to the etacism of Erasmus. See Etacism.
   [1913 Webster]

         In all such questions between [epsilon] and
         [alpha][iota] the confusing element of itacism comes
         in.                                      --Alford.
   [1913 Webster]