Curving of the fifth finger (the little finger) toward the fourth finger (the ring finger).

Sometimes it is called the "fifth finger clinodactyly" to distinguish it from a similar curving of other fingers or toes.

Clinodactyly is considered a minor congenital malformation (birth defect). The basis for the clinodactyly is that the middle bone in the fifth finger is underdeveloped and, instead of being rectangular, is wedge-shaped.