Anoka County (/əˈnoʊkə/ ə-NOH-kə) is the fourth-most populous county in the U.S. state of Minnesota. As of the 2010 census, the population was 330,844. The county seat and namesake of the county is the City of Anoka, which is derived from the Dakota word anokatanhan meaning "on (or from) both sides," referring to its location on the banks of the Rum River.