Where it sits
Synecdoche sits at the far left. Almost every argument about the two happens in the middle.
Tell it apart
What it doesn't mean
It is the ordinary operating mode of news, law and business language. 'Downing Street said', 'Wall Street reacted', 'the bench ruled', 'the label dropped them' — none of these are figures of speech being deployed. They are simply how institutions are referred to, and the alternative phrasing would be unusable.
The distinction has been disputed since antiquity. Some rhetoricians treat synecdoche as a SPECIES of metonymy; others keep them separate; and a classical strand, Quintilian's, folds both under metaphor as conceptual substitution — where modern theory after Jakobson does the reverse, setting metaphor and metonymy against each other as the two poles of trope. Handbooks contradict each other, and have done for two thousand years.
What it really means
Greek: a change of name. Meta- + onoma. The definition is the operation, and the Greek deliberately does not say what kind of association qualifies — which is why the boundary with synecdoche has been argued about for two thousand years and remains open.
But the important thing about metonymy is not that it is a figure of speech. It is that it is how public language actually works.
Downing Street said. Wall Street reacted. The bench ruled. The label dropped them. The Pentagon confirmed. None of these are ornamental. They are the default, unmarked way of referring to institutions, and rewriting them literally produces sentences nobody could use — an unnamed official authorised to speak on behalf of the office of the Prime Minister said.
Which is where it becomes worth watching rather than admiring.
Metonymy removes the actor. The White House said names no speaker. Wall Street panicked names nobody who panicked. The market decided attributes a decision to a thing incapable of deciding. Every one of those constructions is convenient, standard, and quietly disperses responsibility into a building, a street, or an abstraction.
Sometimes that is honest — a large institution genuinely does act in ways no individual chose. Sometimes it is doing work that a named subject would make visible.
On the technical dispute, the cleanest available rule: metonymy substitutes something associated, where the two things are genuinely different objects — a crown is not part of a monarch. Synecdoche substitutes a part for a whole, where the two are the same thing at different scales.
Useful. Also contested since antiquity, with some rhetoricians treating synecdoche as a species of metonymy, some keeping them apart, and a classical strand, Quintilian's, folding both into metaphor. If you find yourself arguing about which one the crown is, you are re-enacting a very old disagreement rather than losing one.
Where it comes from
Greek — change
Greek — name
Literally 'a change of name'. The Greek describes the operation with no reference to what kind of association is involved — which is why the boundary with synecdoche was left open from the start.
- antiquity
Classical rhetoric establishes metonymy as a trope alongside metaphor, synecdoche and irony; grouping those four as the 'master tropes' is Kenneth Burke's, from A Grammar of Motives (1945).
- 1560s
The term is in recorded English rhetorical use.
In real life
- 'The kettle's boiling,' she called. Strictly speaking it was the water, but the container stands in for its contents.
- Hollywood is nervous about the strike, says the headline. It means the film industry, named after the district that houses it.
- He's been hitting the bottle again. Nobody hits a bottle; the bottle stands for what is in it, and for the habit.
Questions
Q01How is it pronounced?
mih-TON-ih-mee — stress on the second syllable, like 'economy' with an m.
Q02Is synecdoche a kind of metonymy?
Depends who you ask, and that has been true since antiquity. Some classical and modern rhetoricians class it as a species of metonymy; others keep them distinct. Neither position is an error.
Q03Why does it matter?
Because metonymy quietly relocates responsibility. 'The White House said' has no speaker; 'Wall Street panicked' has no panicking person. Institutions get to act without anyone acting.