The white half-moon on your nail is called lunula and is a very important part of our body. It is extremely sensitive, and some experts say that its size can be a possible cause of various diseases. If the half-moon isnon- existent or is reduced, this may point to possible diseases.
In Latin lunula means “little moon,” but it is actually the visible part of the nail root. It is most noticeableon the thumb. The white color of lunula is apparent because the fifth basal layer of the epidermis is hiding underneath the blood cells.