This is a list of U.S. county name etymologies, covering the letters N to R.

N County name State Origin Nacogdoches County Texas Named for the Nacogdoche tribe of Caddo Native Americans. Nance County Nebraska Named after Governor Albinus Nance."Nance County". Nebraska Association of County Officials. Retrieved 2010-05-25. Town and County of Nantucket Massachusetts Nantucket takes its name from a word in an Eastern Algonquian language of southern New England, originally spelled variously as natocke, nantaticut, nantican, and nautican. The meaning of the term is uncertain, although it may have meant "in the midst of waters," or "far away island."Huden, John C. (1962). Indian Place Names of New England. New York: Museum of the American Indian. Cited in: Bright, William (2004). Native American Place Names in the United States. Norman: University of Oklahoma Press, pg. 312 Napa County California Named for the city of Napa, California, which takes its name from a southern Nappan village. Nash County North Carolina Named for Brigadier General Francis Nash, who had been mortally wounded at the Battle of Germantown. Nassau County Florida Named for the Duchy of Nassau in Germany. Nassau County New York Named after an old name for Long Island, which was named Nassau after William of Nassau, Prince of Orange (who later became King William III of England.) Natchitoches Parish Louisiana Named for the Natchitoches tribe of Native Americans. Natrona County Wyoming Named for the natron (soda) deposits in the county. Navajo County Arizona named for the Navajo. Navarro County Texas Named for José Antonio Navarro, a Tejano leader in the Texas Revolution who signed the Texas Declaration of Independence. Nelson County Kentucky Named for Thomas Nelson, Jr. a Virginia Governor who signed the Declaration of Independence. Nelson County North Dakota for Nelson E. Nelson, a ND legislator at the time. Nelson County Virginia Named for Thomas Nelson, Jr. a Virginia Governor who signed the Declaration of Independence. Nemaha County Kansas Chiwere word ñí-máha 'murky water.' Nemaha County Nebraska Chiwere word ñí-máha 'murky water.' Neosho County Kansas Neosho River, from the Osage meaning 'cold, clear water' or 'main river,' Neshoba County Mississippi Nashoba, a Choctaw chief, derived from the Choctaw word nashoba, means Wolf. Ness County Kansas Named for Corporal Noah V. Ness of the 7th Kansas Cavalry Regiment (US Army). Ness died of wounds suffered at the Battle of Abbeyville in Mississippi in August 1864.Kansas Place-Names, John Rydjord, University of Oklahoma Press, 1972, Nevada County Arkansas The state of Nevada, which it resembles in shape. Nevada County California named after the mining town of Nevada City, a name derived from the term "Sierra Nevada." The word nevada in Spanish means "snowy" or "snowcovered." New Castle County Delaware William Cavendish, 1st Duke of Newcastle-upon-Tyne, courtier. New Hanover County North Carolina Named for the House of Hanover. New Haven County Connecticut Named after its largest city and county seat, New Haven. New Kent County Virginia The county of Kent, England. New London County Connecticut Named after the county seat, New London, which is named for London, England. New Madrid County Missouri Named after a district located in the region that was once under Spanish rule, Nuevo Madrid, after the city of Madrid, Spain. New York County New York New York is named after James, Duke of York, who renamed New Amsterdam after himself shortly after the British takeover in 1664. The county name also refers to the fact that New York City was wholly contained in the county until it combined with other areas in the 1880s. New York County today is thus simply referred to as Manhattan, the island that forms almost all the area of the county. Newaygo County Michigan Derived from then name of a Chippewa chief who signed the Treaty of Saginaw or from a Algonquian word meaning "much water." Newberry County South Carolina Unknown; possibly named for Newbury, Berkshire, England. Newport County Rhode Island Descriptive, recalling Newport, Monmouthshire, Wales City of Newport News Virginia Not known with any certainty. See the "Name" section of the city's article for possibilities. Newton County Arkansas Named for Thomas W. Newton, an Arkansas Congressman. Newton County Georgia Named after Sgt. John Newton of the American Revolutionary War. Newton County Indiana Newton County Mississippi Named for Sir Isaac Newton, physicist. Newton County Missouri Named after Sgt. John Newton of the American Revolutionary War. Newton County Texas Nez Perce County Idaho Named for the Nez Percé tribe of Native Americans. Niagara County New York Derived from the Indian word Onguiaahra meaning the straight or thunder of waters.Retrieved 2010-05-25 Nicholas County Kentucky Named for George Nicholas, the "Father of the Kentucky Constitution". Nicholas County West Virginia Named for Virginia Governor Wilson Cary Nicholas. Nicollet County Minnesota Named for Joseph Nicolas Nicollet, a geographer-explorer. Niobrara County Wyoming Omaha–Ponca languageIndian 'spreading water river.' Noble County Indiana Named for James Noble, the first U.S. Senator from Indiana. Noble County Ohio Named for Rep. Warren P. Noble of the Ohio House of Representatives, who was an early settler there. Noble County Oklahoma for John W. Noble, Secretary of the Interior Nobles County Minnesota Named for William H. Nobles, a member of the Territorial Legislature. Nodaway County Missouri Named for the Nodaway River, from the Chiwere Nyi At'ąwe, "jump over water." Nolan County Texas Named for Philip Nolan, one of the first American traders to visit Texas. Nome Census Area Alaska Named for Nome, Alaska. City of Norfolk Virginia Named for the county of Norfolk, England. Norfolk County Massachusetts Norman County Minnesota In honor of the large number of Norwegians (endonym nordmenn), who settled in this county. North Slope Borough Alaska Named for the Alaska North Slope, a region on the northern slope of the Brooks Range. Northampton County North Carolina Named for James Compton, 5th Earl of Northampton. Northampton County Pennsylvania Northamptonshire, England, Northampton County Virginia for Spencer Compton, 2nd Earl of Northampton Northumberland County Pennsylvania Named for the county of Northumberland, England. Northumberland County Virginia Northwest Arctic Borough Alaska Named for its location in the northwest Arctic region of Alaska. City of Norton Virginia Named in 1890 after Eckstein Norton, then president of the Louisville & Nashville Railroad. Norton County Kansas Named for Orloff Norton. Nottoway County Virginia From the Nottoway people. Nowata County Oklahoma From the Lenape word nuwita, meaning "friendly" or "welcome." Noxubee County Mississippi Derived from the Choctaw word nakshobi, meaning to stink. Nuckolls County Nebraska Named after Stephen F. Nuckolls, an early pioneer in this area. Retrieved 2010-05-25. Nueces County Texas Named for the Nueces River, whose name comes from the Spanish word for walnuts or pecans. Nye County Nevada Named in honor of James W. Nye, first governor of the Nevada Territory and later U.S. Senator from the state.

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