Dardenne Prairie was originally a prairie region which began in the area near St. Peters, Missouri and extended north of Dardenne Creek, almost to Peruque Creek. The area was so named after the stream. In early documents the name appeared as Dardonne Creek, Darden Creek, Dardenne River, or Dardonne River. In Houck's history of 1908, Dardene River is also found.

Dardenne is said to be a corruption of the French "Terre d'Inde", meaning "the land of turkeys".Terre d'Inde actually translates to "Land of India". "Turkey Land" on the other hand in French is Terre des Dindons so the above explanation is not plausible. A better explanation is that the name was borrowed from the Dardenne family, early pioneers in the Mississippi Valley. "A Touissant Dardenne from Montreal, Canada, married Marie Francoise Lever, 'veuve de feu Michal Vieu,' at St. Anne de Fort Chartres, November 21, 1747. One of these Dardennes may have first camped and hunted on this creek and thus given it his name." Touissant Dardenne, at Fort de Chartres on this matrimonial occasion, was still several hundred miles nearer to the creek he was supposed to have named than any other person named Dardenne. No one by the name of Dardenne has ever owned land in St. Charles County, either under Spanish dominion, or since the transfer. There is, of course, no reason why this creek, heavily wooded throughout its course, could not, by some French trapper, have been named Dardenne (or d'Ardenne in French) in memory of the Ardennes on the river Meuse in French Flanders.

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