The story
In 1893, a petition was filed with the U.S. Postal Service for the area’s first post office, to be named “Toluca Post Office”. General Charles Forman, a wealthy local landowner and one of the proponents of the petition, later stated that he had chosen the name “Toluca” from a Paiute word meaning “fertile” or “beautiful” valley.
Etymology from Wiktionary, CC BY-SA 4.0.