<unk>  are deep grooved lines that run from side to side on the fingernail or the toenail. They may look like indentations or ridges in the nail plate. This condition of the nail was named by a French physician, Joseph Honoré Simon<unk>  (1806–1865), who first described it in 1846.
Beau's lines
Pastia's lines
Gilula's lines
Langer's lines
Blaschko's lines
Schwalbe's line
Dandy's point
Burton's line