is a town in Rockingham County, New Hampshire, United States. The population was 34,021 at the 2000 census. Although it is a town and not a city, Derry is the fourth most-populous community in New Hampshire.
The primary settlement in town, where over 66% of the population resides, is defined by the U.S. Census Bureau as the Derry census-designated place (CDP) and includes the densely-populated portions of the town centered on the intersection of New Hampshire Route 28 and New Hampshire Route 102.
Although it was first settled by Scottish-Irish (also known as Ulster-Scots) families in 1719, Derry was not incorporated until 1827. It was for a long time part of Londonderry, which included Windham and portions of Manchester, Salem and Hudson. The town was named for the city of Derry, Northern Ireland, the Irish word "Doire" meaning "oak woods." The first potato planted in the United States was planted here in 1719. The town is the location of two of America's oldest private schools, Pinkerton Academy, founded in 1814 and still in operation, and the closed Adams Female Seminary.
Derry was once a linen and leather-making center until New England textile industries moved south in the 20th century. As recently as World War II, Derry was also a sleepy farming community. The post-war suburban boom, the town's proximity to Boston in the south and Manchester to the northwest, and the construction of Interstate 93 through town led to a huge population boom. Although this growth has slowed somewhat, the population of Derry still increased by 15 percent during the 1990s.