Definition - A figure of speech where the speaker deviates from expected word patterns.
Note: As opposed to a trope, which deviates from the expected meaning.

Example -
The phrase Dave, my friend's best friend uses the scheme called apposition . It deviates from the expected pattern by omitting the word is.

Etymology -
It derives from the Greek schema, form or shape.

Oxford English Dictionary -
Its first citation is from 1553:
"I might tary a longe time in declaryng the nature of diuerse Schemes, whiche are woordes or sentencies altered … contrarie to the vulgare custome of our speache."
(T. Wilson Rhetoric, 94)

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