Nevada is a city in and the county seat of Vernon County, Missouri, United States. The population was 8,386 at the 2010 census, and 8,254 in t…Nevada is a city in and the county seat of Vernon County, Missouri, United States. The population was 8,386 at the 2010 census, and 8,254 in the 2018 estimate. The local government has a council-manager model.