Armour is a city in and the county seat of Douglas County, South Dakota, United States. The population was 699 at the 2010 census.
Armour was founded in 1885. The city was named for Philip D. Armour, who was founder of Armour and Company, a meat packing company. Contrary to popular belief, Armour was never home to a meat packing plant; the town was so named because Mr. Armour was also the chairman of the railroad that went through Armour and donated a bell to the local congregational church. The athletic teams of Armour High School were formerly known as the "Packers" in reference to the well known packing company, although today the high school plays its sports jointly with Tripp-Delmont High School as the "Tripp-Delmont/Armour Nighthawks."
Armour is located at 43°19′10″N 98°20′50″W / 43.31944°N 98.34722°W / 43.31944; -98.34722 (43.319410, -98.347342).