A suburb is an area within a metropolitan area which is predominantly residential and within commuting distance of a large city. Suburbs can have their own political or legal jurisdiction, especially in the United States, but this is not always the case, especially in the United Kingdom, where most suburbs are located within the administrative boundaries of cities. In most English-speaking countries, suburban areas are defined in contrast to central city or inner city areas, but in Australian English and South African English, suburb has become largely synonymous with what is called a "neighborhood" in the U.S. Due in part to historical trends such as white flight, some suburbs in the United States have a higher population and higher incomes than their nearby inner cities.

उपनगर (suburb) या उपनगरीय क्षेत्र ऐसा आवासीय क्षेत्र या मिश्रित व्यापारिक-व-आवासीय क्षेत्र होते है जो अपने से बड़े किसी नगर के इतना समीप स्थित हो जिस से नगर और उपनगर के बीच सरलता से आना-जाना आसान हो। कई उपनगरों का अपना अलग प्रशासन होता है लेकिन मोटे तौर पर उनकों अपने मुख्य नगर के विस्तारित नगरीय क्षेत्र से सम्बन्धित ही माना जाता है। उदाहरण के लिए ग़ाज़ियाबाद को दिल्ली का उपनगर माना जाता है।