Onychomycosis (also known as dermatophytic onychomycosis or tinea unguium) is a fungal infection of the nail.
It is the most common disease of the nails and constitutes about half of all nail abnormalities. This condition may affect toenails or fingernails, but toenail infections are particularly common.
Onychomycosis is a fungal infection of the toenails or fingernails that may involve any component of the nail unit, including the matrix, bed, or plate.