from The American Heritage® Dictionary of the English Language, 4th Edition
- A historical overland route to the western United States extending from various cities on the Missouri River to the Oregon Country and later Oregon Territory. The trail was opened in 1842, and by 1845 more than 3,000 migrants had made the arduous journey. After the coming of the railroad, the trail fell into disuse and was finally abandoned in the 1870s.
Sorry, no etymologies found.