Definition - A change in grammatical structure within the same sentence. Grammar-wise, it is a solecism; rhetoric-wise, it is a type of emphasis.

1. In texts the change is often signalled with a dash.
2. Contrast this with aposiopesis, where the sentence peters out before it is complete.

Example -
I warned him that if he didn't stop living in the past — what would the future be?

Etymology -
The word derives from the Greek anakolouthos, does not follow (from an, not + akolouthos, following). The equivalent Latin term is non sequitur.

Oxford English Dictionary -
Its first citation is from 1706:
"Anacolython, a Rhetorical Figure, when a Word that is to answer another is not express'd."
(Phillips, The New World of Words )

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