Fontanel

Either of two gaps between the bones of the skull that close between the age of 6 months and two years, especially the larger one. The larger fontanel, the fontanel gate or forehead fontanel (called anterior fontanel in Western medicine) is located just in front of the vertex; the smaller one, called pillow fontanel (called the posterior fontanel in Western medicine), is on the back of the head. The main diseases associated with the fontanels are ununited skull (nonclosure of the fontanels), bulging fontanel gates, and depressed fontanel gates.

Etymology

Chin 囟 xìn is a pictographic representation of the skull with nose and sutures. Eng from MF. fontanele, a little spring or fountain.