1. One of the thin, horny, translucent plates covering the dorsal surface of the distal end of each terminal phalanx of fingers and toes. A nail consists of corpus or body, the visible part, and radix or root at the proximal end concealed under a fold of skin. The underpart of the nail is formed from the stratum germinativum of the epidermis, the free surface from the stratum lucidum, and the thin cuticular fold overlapping the lunula representing the stratum corneum.
2. A rod of metal or other solid substance, used in operations to fasten together the fragments of a broken bone.
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