Methuen, town, Essex County, northeastern Massachusetts, on the Merrimack River, near Lawrence; settled 1666, incorporated as a town 1725, reincorporated 1921. Major manufactures are cotton textiles and electronic equipment. In December 1995 a fire destroyed the Malden Mills textile plant, the town's largest employer, putting 1400 people out of work, but the factory's owner pledged to rebuild it. Originally part of Haverhill, the community was separately incorporated in 1725. It is named for the English diplomat Sir Paul Methuen. Population 36,701 (1980); 39,990 (1990); 43,789 (2000).