The French term mannequin (model) dates back to the 19th century. At that time, a mannequin was a wickerwork dummy, used to showcase ready-to-wear for female shoppers. Within two decades, that task was given to real women. Before long, these “models” were synonymous with Paris fashion. “Without the model,” says Sylvie Lécallier of the Musée Galliera, “there would never be fashion as we know it today.” That universe of style is the subject of her museum’s new show, “Model: The Body of Fashion,” which runs at les Docks until May 19.