Minnehaha County is a county located in the state of South Dakota. As of the 2010 census, the population was 169,468, making it the most populous county in South Dakota. Its county seat is Sioux Falls. The county received its name from the Sioux Indian word "Mnihaha", which is often incorrectly translated as "laughing water," but in reality it translates into "rapid water," or "waterfall." The original word was altered to its current spelling, thus making pronunciation easier.
Minnehaha County is part of the Sioux Falls, SD Metropolitan Statistical Area.