malformation

The condition of being malformed; deformity.

A body part that is malformed; a deformity.

Faulty formation; irregular or anomalous formation or structure, especially in a living body; a deviation from the normal form or structure either in the whole or in part of an organ. Also, until recently, maleformation.

Ill formation; irregular or anomalous formation; abnormal or wrong conformation or structure; -- often used of body parts such as limbs which do not develop properly during fetal maturation.

An abnormal formation.