A synecdoche (/s??n?kd?ki?/, si-NEK-d?-kee; from Greek ????????? synekdoche, meaning "simultaneous understanding"[1]) is a figure of speech in which a term for a part of something refers to the whole of something, or vice versa.[2]
A synecdoche is a class of metonymy, often by means of either mentioning a part for the whole, or conversely the whole for one of its parts. Examples from everyday English-language idiomatic expressions include "bread and butter" for "livelihood", "suits" for "businessmen", "boots" for "soldiers", etc.[3] It is also often used in government announcements where a building stands in for a government official or agency, such as "No. 10" or "No. 10 Downing Street," the address of same, being used to represent the British Prime Minister, or "The Pentagon," the building housing its headquarters, to represent the United States Department of Defense.
Synecdoche is often used as a type of personification, by attaching a human aspect to a non-human thing. This is used in reference to political relations, including "having a footing", used to mean a country or organization is in a position to act, or "the wrong hands", to describe opposing groups, usually in the context of military power.[8]
Synecdoche is a rhetorical trope and a type of figurative speech similar to metonymy—a figure of speech in which a term that denotes one thing is used to refer to a related thing.[4][5] Indeed, synecdoche is sometimes considered a subclass of metonymy. It is more distantly related to other figures of speech, such as metaphor.[6]
More rigorously, metonymy and synecdoche can be considered sub-species of metaphor, intending metaphor as a type of conceptual substitution (as Quintilian does in Institutio oratoria Book VIII). In Lanham's Handlist of Rhetorical Terms,[7] the three terms have somewhat restrictive definitions, arguably in tune with a certain interpretation of their etymologies from Greek:
Metaphor: changing a word from its literal meaning to one not properly applicable but analogous to it; assertion of identity rather than, as with simile, likeness.
Metonymy: substitution of cause for effect, proper name for one of its qualities, etc.
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