John L. Sullivan means in slang: Americans tend to think of Sullivan as the world’s heavyweight champion. However, many boxing historians consider him a U.S. champ. He lost his only match with Charley Mitchell, an English pugilist, at Chantilly Oise, Fr. on March 10, 1888. It ended in a draw after 39 rounds. (in Slang Dictionary, added by Jaylan Sawyer)