A synecdoche (/s??n?kd?ki/ sin-NEK-t?-kee,[1] from Greek ?????????, synekdoch?, ‘simultaneous understanding’)[2] is a figure of speech in which a term for a part of something refers to the whole of something or vice versa.[3][4][5][6]

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 common English expressions include “suits” (for “businessmen”), “boots” (for “soldiers”) (pars pro toto), and “America” (for “the United States of America”, totum pro parte).[7]

The use of government buildings to refer to their occupants is metonymy and sometimes also synecdoche. “The Pentagon” for the United States Department of Defense can be considered synecdoche, as the building can be considered part of the department. Likewise, using “Number 10” to mean “the Office of the Prime Minister” (of the United Kingdom) is a synecdoche.

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