A-line
From The Fashion Dictionary
The word a-line is a fashion term that is used to describe a dress or a skirt that is narrow at the top and flares gently towards the bottom, thus resembling the letter A. An a-line dress or skirt looks good on all silhouettes, but works particularly well for heavy bottomed figures.[1]
The Origin of the Word A-line
The term a-line was coined by French couture designer Christian Dior in 1955 when he introduced his Spring-Summer collection that included a lot of a-line skirts and dresses. This collection was a follow-up to his h-line collection for the Fall-Winter season.