1. or Newcastle upon Tyne (tīn) A city of northeast England on the Tyne River north of Leeds. Founded as a Roman military station, it became a coal-shipping port in the 1200s. Its prominence in the trade gave rise to the expression to carry coals to Newcastle, meaning "to do something superfluous or unnecessary."
2. A city of southeast Australia northeast of Sydney. Like the English city for which it was named, it is a coal-shipping port.