trope

from The American Heritage® Dictionary of the English Language, 5th Edition.

• noun A figure of speech using words in nonliteral ways, such as a metaphor.
• noun A word or phrase interpolated as an embellishment in the sung parts of certain medieval liturgies.

from The Century Dictionary.

• noun In rhetoric, a figurative use of a word; a word or expression used in a different sense from that which properly belongs to it, or a word changed from its original signification to another for the sake of giving spirit or emphasis to an idea, as when we call a stupid fellow an ass, or a shrewd man a fox.
• noun In Gregorian music, a short cadence or closing formula by which particular melodies are distinguished. Also called differentia and distinctio.
• noun In liturgics, a phrase, sentence, or verse occasionally accompanying or interpolated in the introit, Kyrie, Gloria in Excelsis, Sanctus, and Agnus Dei in different parts of the Western Church. Since the sixteenth century tropes have no longer been used.
• noun A geometrical singularity, the reciprocal of a node.

from the GNU version of the Collaborative International Dictionary of English.

• noun The use of a word or expression in a different sense from that which properly belongs to it; the use of a word or expression as changed from the original signification to another, for the sake of giving life or emphasis to an idea; a figure of speech.
• noun The word or expression so used.

from Wiktionary, Creative Commons Attribution/Share-Alike License.

• noun literature Something recurring across a genre or type of literature, such as the ‘mad scientist’ of horror movies or ‘once upon a time’ as an introduction to fairy tales. Similar to archetype and cliché but not necessarily pejorative.
• noun A figure of speech in which words or phrases are used with a nonliteral or figurative meaning, such as a metaphor.
• noun music A short cadence at the end of the melody in some early music.
• noun music A phrase or verse added to the mass when sung by a choir.
• noun music A pair of complementary hexachords in twelve-tone technique.
• noun Judaism A cantillation.
• verb To use, or embellish something with a trope.

from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.

• noun language used in a figurative or nonliteral sense