In fashion, the midriff is the human abdomen which can be exposed when a woman wears a crop top or some skimpy deisgns of swimwear or underwear. A Cholis worn by Indian women exposes a section of a woman's midriff - usually 4 to 5 inches of bare skin.
Midriff is now most commonly encountered in the mid-torso or clothing-related senses. These senses are relatively young, having appeared, respectively, in the early 19th and mid-20th centuries.