Paraprosdokian

A paraprosdokian n is a figure of speech in which the latter part of a sentence, phrase, or larger discourse is surprising or unexpected in a way that causes the reader or listener to reframe or reinterpret the first part. It is frequently used for humorous or dramatic effect, sometimes producing an anticlimax. For this reason, it is extremely pop...
Found on http://en.wikipedia.org/wiki/Paraprosdokian

Paraprosdokian

surprise or unexpected ending of a phrase or series.
*He was at his best when the going was good. Alistair Cooke on the Duke of Windsor
*There but for the grace of God -- goes God. Churchill
*Laudandus, ornandus, tollendus. Cicero on Octavian
Found on http://www.uky.edu/AS/Classics/rhetoric.html
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