Not to be confused with Lyon, Missouri.
A variant name was "Delto". A post office called Delto was established in 1874, the name was changed to Lyon in 1913, and the post office closed in 1928. The present name honors the Lyons family, local merchants.
- U.S. Geological Survey Geographic Names Information System: Lyons
- "Post Offices". Jim Forte Postal History. Retrieved 24 October 2016.
- "Laclede County Place Names, 1928–1945 (archived)". The State Historical Society of Missouri. Retrieved 24 October 2016.