Marlboro or Marlborough (märlˈbərō) [key], city (1990 pop. 31,813), Middlesex co., E Mass.; settled on the site of a Native American village 1657, inc. as a city 1890. A shoe-manufacturing center for many years, Marlboro now produces plastic and paper products, sporting goods, computer equipment, and chemicals. It is also a commercial and business center. The community was almost destroyed (1676) in King Philip's War.