Final answer:
The visible portion of a nail is known as the nail plate or nail body. It is surrounded by the nail fold and nail cuticle and is on top of the nail bed. The nail plate's growth begins at the nail root.
Step-by-step explanation:
The name given to the visible portion of a nail is the nail plate, also commonly referred to as the nail body. The nail plate is the hard part of the nail, made of keratin, which is a protein that forms the cells of the nails and provides them with strength. The nail plate lies on top of the nail bed, a specialized structure of the epidermis, which appears pink due to blood vessels.
Around the nail plate are the nail fold and the nail cuticle, also called the eponychium. The nail fold is the fold of skin around the sides of the nail plate, and the nail cuticle is the fold that meets the proximal end of the nail body. Together with the nail root, the part of the nail under the surface of the skin where growth begins, these structures contribute to the formation and protection of the nail plate.
Moreover, the visible white crescent at the base of the nail is called the lunula. The portion of the nail that extends beyond the fingertip, known as the free margin, is what typically gets trimmed when maintaining nail length.