In rhetoric and cognitive linguistics, metonymy (in Greek meta = after/later and onoma = name) is the use of a single characteristic to identify a more complex entity. It is also known as denominatio or pars pro toto (part for the whole).

In rhetoric, metonymy is the substitution of one word for another with which it is associated. Metonymy works by contiguity rather than similarity. Typically, when someone uses metonymy, they don't wish to transfer qualities (as you do with metaphor); rather they transfer associations which may not be integral to the meaning.

The common figure "The White House said..." is a good example of metonymy, with the term "White House" actually referring to the authorities who are symbolized by the White House, which is an inanimate object that says nothing. The Crown for a kingdom is another example of this kind of metonymy. Metonymy can also refer to the rhetorical strategy of describing something indirectly by referring to things around it: describing someone's house in order to describe them, for example. Advertising frequently uses this kind of metonymy, simply putting a product in close proximity to something we want (beauty, happiness). See also figure of speech, synecdoche, metalepsis.

In cognitive linguistics, metonymy is one of the basic characteristics of cognition. It is extremely common for people to take one well-understood or easy-to-perceive aspect of something and use that aspect to stand either for the thing as a whole or for some other aspect or part of it. For example,

The pen is mightier than the sword.

"Pen" denotes publishing and "sword" denotes military force.

In linguistics, as in rhetoric, the distinction between metaphor and metonymy is important. For example, the phrase "to fish pearls" uses metonymy, drawing from "fishing" the notion of taking things from the ocean. What remains similar is the domain of usage and the associations, but we understand the phrase in spite of rather than because of the literal meaning of fishing: we know you do not use a fishing rod or net to get pearls. In contrast, the metaphorical phrase "fishing for information", transfers the concept of fishing (waiting, hoping to catch something) into a new domain. (example drawn from Dirven, 1996)

See also

Social stereotype, synecdoche

References

Dirven, René "Conversion as a Conceptual Metonymy of Basic Event Schemata." Workshop on Metonymy, Hamburg University, Germany, June 23-24, 1996. http://www.psyc.leeds.ac.uk/cgi-bin/search/metaphorAbstracts/abstract.pl?DirvenR02

metaphorik.de 06/2004 (online journal about metaphor and metonymy) special issue: metonymy. http://www.metaphorik.de/06