Black Cocktail Dresses - Sometimes referred to as a “party dress,” a black cocktail dress is a mid-length semi-formal dress that is often chosen for evening outings. Although the style of dress itself emerged during the 1920s, The classic black cocktail dress defined by Coco Chanel is a type of cocktail dress, and is often touted as a versatile must-have for any woman’s wardrobe. One of the most iconic images of the black cocktail dress in popular culture is that worn by Audrey Hepburn in the 1961 film, Breakfast at Tiffany’s.