Reduced size owing to the underdevelopment of all or part of an organ (see figure below for an example).
Moderate to severe hypoplasia in a child with the Goldenhar-Golin syndrome (also known as Oculuoauricular dysplasia), which is a congenital birth defect involving deformities of the face, usually on one side. It is a rare congenital anomaly about which its etiology is still unknown. In some cases the physical irregularities are bilateral. First reported by Maurice Goldenhar (1924-2001) in 1952.
See Aortic hypoplasia, Dysplasia, Hypomorphic nervous system