The term 'Wabash Cannonball, for one' is a reference to a popular American folk song of the same name. The song is about a fictional TRAIN that travels from the Wabash River in Indiana to the Ohio River. The crossword solution for this term is 'TRAIN', which is a five-letter word. The Wabash Cannonball was a real TRAIN that ran from 1881 to 1971 and was operated by the Wabash Railroad. It was one of the most famous trains in the United States and was known for its speed and reliability.