What is the white part of your nail?
The lunula ("small moon") is the visible part of the matrix, the whitish crescent-shaped base of the visible nail. The lunula can best be seen in the thumb and may not be visible in the little finger.
What is the white, crescent part of your nail?
lunulae lunula
Nail (anatomy)
In the mid-1970s, Pink was tasked by a film director to come up with a universal nail look that would save screen actresses from having to spend time getting their nails redone to go along with their costume changes. Inspired by the instant brightening effect of a white pencil applied to the underside, Pink suspected that the solution was to apply that same neutralizing principle to the top of the nail. "I got one gallon of white polish for the tips, and pink, beige, or rose for the nail," he recalled in a 2014 interview with "The National".
What is the white, top part of your nail?
tips tip
Manicure
Manicure
https://en.wikipedia.org/wiki/Manicure
Nail (anatomy)
https://en.wikipedia.org/wiki/Nail%20%28anatomy%29
A nail is a claw-like plate at the tip of the fingers
Nail (anatomy)
The lunula, or lunulae (pl.) (from Latin 'little moon'), is the crescent-shaped whitish area of the bed of a fingernail or toenail.
Lunula (anatomy)
It is located at the end of the nail (that is closest to the skin of the finger), but it still lies under the nail. It is not actually white but only appears so when it is seen through the nail. Outlining the nail matrix, the lunula is a very delicate part of the nail structure. 
Lunula (anatomy)
A nail is a claw-like plate at the tip of the fingers or toes, and the lunula is the crescent-shaped whitish area of the bed of a fingernail or toenail. The lunula is located at the end of the nail that is closest to the skin of the finger; however, it still lies under the nail. The lunula is not actually white but only appears so when it is seen through the nail. Outlining the nail matrix, the lunula is a very delicate part of the nail structure. The lunula can best be seen in the thumb and may not be visible in the little finger.