diastema

noun

1. A gap or space between two adjacent teeth, especially the upper front incisors (in humans).

   “A gormless-looking boy, thin and exhibiting diastemata in the shop-front lights, offered him English newspapers.”

2. A gap between teeth of different types, e.g. incisors and molars, which is a feature of some rodents and ungulates.
3. Any abnormal space, fissure, or cleft in an organ or other part of the body.
4. The modified protoplasm at the equator of a cell, existing before mitotic division.