Metonymy
A figure that names a thing through another logically linked to it: container for content, author for work.
Metonymy replaces a word with another linked to it by a constant logical relation: container for content ("drink a glass"), author for work ("reading a Dickens"), place for institution ("the White House responded"), cause for effect, symbol for thing. Unlike metaphor, which rests on resemblance, metonymy rests on contiguity — both realities belong to the same world.
It's an economy device, ubiquitous in everyday speech, but it becomes a powerful stylistic tool when chosen deliberately: calling doctors "white coats" installs a point of view, almost a sociological distance. Metonymy directs the gaze as much as it abbreviates.
Example
"Drink a glass," "reading a Dickens," "the Crown decided."