During the Victorian era, layers of fabric denoted wealth, so the overskirt (or polonaise) was hemmed short to reveal tiered layers of ruffle petticoats underneath. These ruffles were known as 'flounce' when they appeared on the polonaise or overskirt, along with dramatic swag and draping. Long tiered skirts are often used in Steampunk fashion, either as overskirts or underskirt/petticoats. There's also a shorter, modern variation known as the ruffle skirt.