noun
- A river that rises in northeastern South Dakota and flows southward to join the Missouri River at Sioux City, Iowa. .
WordNet 3.0 © 2006 by Princeton University
| APA | WordNet. (2010). big sioux river. Retrieved September 21, 2026, from http://smartdefine.org/big_sioux_river/definitions/1324325 |
| Chicago | WordNet. 2010. "big sioux river" http://smartdefine.org/big_sioux_river/definitions/1324325 (accessed September 21, 2026). |
| Harvard | WordNet 2010, big sioux river, Smart Define, viewed 21 September, 2026, <http://smartdefine.org/big_sioux_river/definitions/1324325>. |
| MLA | WordNet. "big sioux river" 23 October 2010. Web. 21 September 2026. <http://smartdefine.org/big_sioux_river/definitions/1324325> |