The main leader of an organization or undertaking, the chief. Top banana comes from vaudeville, where the term denoted the starring comedian. Possibly it originally alluded to an individual who used bananas in his or her act. The 1954 film Top Banana, starring Phil Silvers, features a television comic and uses a great many vaudeville jokes. (A related term is second banana, for a supporting comedian, usually the straight man. However, it has not been as widely extended to other venues and cannot be considered a cliché.) Top dog came from sports in the late 1800s and alluded to the dog who wins in a dogfight (emerges on top); it was quickly extended to the winner or favorite in other competitions, and eventually simply to the principal leader.