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The Collaborative International Dictionary
Itacism

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.

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

Wiktionary
itacism

n. (alternative form of iotacism English)