Metonymy

Metonymy names something by way of a thing closely associated with it rather than by its own name — 'the crown' for the monarchy, 'the bench' for the judiciary — so the association does the work of the definition.

The crown refused. No physical crown refused anything; the word stands in for the monarch, and the substitution carries an extra idea with it — that what refused was an institution rather than a person.

That extra idea is the point. Metonymy is not a decorative swap. The thing chosen to stand in tells the reader how to feel about the thing itself.

• The suits are here. — not executives, but executives seen as interchangeable.
• She read it in the trades. — the industry, and the speaker belongs to it.
• He spent thirty years on the shop floor. — a place standing in for a whole working life.

It is closely related to synecdoche, which uses a part for a whole rather than an associate for the thing. All hands on deck is synecdoche; the crown refused is metonymy. The two are commonly treated as one family, and little hangs on the boundary.

Metonymy is quietly one of the most useful devices in fiction, because it is the mechanism behind show, don't tell working at the level of a single word. A marriage rendered as two chairs and one cup on the draining board is metonymy. The abstraction never gets named, and the reader arrives at it anyway.