Metonymy is a term for a figure of speech. Metonymy a thing or concept is indirectly named. It is not called by its own name, but by the name of something which is closely related or implicit in the context.
One of the most common metonyms is the use of the capital city of a country to mean the government of that country, which is usually in the capital city. For example, mass media uses the word "Washington" to talk about the federal government and national politics of the United States, Other examples of metonyms often use place names to mean major industries which are based there. For example, the stock markets of the US are located on Wall Street in New York City, so "Wall Street" is used as a general word for the US economy. Here is a list of some well-known metonyms: