1º_ Willy, or also Willie, is diminutive of the name William or Wilhelm, which in Spanish is Guillermo, and in our language it is usually used as its hypocoristic. 2º_ It is the name of an acrobatics for motorcycles, bicycles and also for other vehicles where the vehicles advance on their rear wheels carrying the fronts in the air. It is an anglicism for wheelie, a diminutive of wheel ("wheel"), which has its Spanish version as a horse (for the position of the horse standing on its hind legs and with its hands up). 3º_ In tennis it is called 'willy' or 'great willy' to a play in which the ball is reached just before it sinks in the own area, with its back to the net and hitting with the racket so that it passes between the legs, calculating the direction and momentum so that it crosses the net and sinks in the rival area. The name is taken from the nickname of its creator, tennis player Guillermo Vilas. By some mistake see willi ( mythology ) , willys ( vehicle ) , english / willy ( "penis" ) .