A chiasmus (or, chiasm; pl. chiasmi) is a literary device that presents parallel ideas or terms in a “sandwich” form that resembles a capital X. This is also the symbol for the Greek capital letter chi, hence the name chiasmus.
Many English readers are familiar with parallelism, a literary arrangement where thoughts occur in an AABBCCDD pattern. A chiasmus might express these thoughts in an ABCDDCBA order.1
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