City, theCity, the (also the ˌCity of ˈLondon) British English 
an area in central London where there are many large banks and financial organizations, including the Bank of England and the stock exchange. The City has an area of about one square mile (about 2.5 square kilometres), and it is sometimes called ‘the Square Mile’, especially in newspapers. Its name is sometimes used to mean people who work there and make financial decisions. There is a similar area in New York City called Wall Street: 
The City is optimistic about the outlook for inflation. a firm of City stockbrokers
an area in central London where there are many large banks and financial organizations, including the Bank of England and the stock exchange. The City has an area of about one square mile (about 2.5 square kilometres), and it is sometimes called ‘the Square Mile’, especially in newspapers. Its name is sometimes used to mean people who work there and make financial decisions. There is a similar area in New York City called Wall Street: The City is optimistic about the outlook for inflation. a firm of City stockbrokers