1a large industrial city and port on the River Tyne in northeast England, whose full name is Newcastle upon Tyne. Newcastle used to have a large coal mining and shipbuilding industry, but much of the old industry has now closed down. People from Newcastle are informally called Geordies, and they have their owndialect of English and their own accent (=way of pronouncing words) which is also called Geordie and is easy to recognize.
2a city, port, and important industrial centre in New South Wales, southeast Australia, near where the Hunter River joins the sea
Definition from the Longman Dictionary of Contemporary English Advanced Learner's Dictionary.