An expression that uses language in a nonliteral way, such as a metaphor or synecdoche, or in a structured or unusual way, such as anaphora or chiasmus, or that employs sounds, such as alliteration or assonance, to achieve a rhetorical effect.
American Heritage(R) Dictionary of the English Language, Fifth Edition. Copyright (c) 2011 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.