Aposiopesis
Pronunciation : Ap`o*si`o*pe"sis
Part of Speech : n.
Etymology : [L., fr. Gr. (Rhet.)
Definition : Defn: A figure of speech in which the speaker breaks off suddenly, as if unwilling or unable to state what was in his mind; as, "I declare to you that his conduct -- but I can not speak of that, here."
Source : Webster's Unabridged Dictionary, 1913