A rare, non-syndromic respiratory or mediastinal malformation characterized by unilateral complete absence of lung tissue, bronchi, and pulmonary vessels. It may be isolated or associated with congenital malformations, most commonly with heart anomalies. Presentation is highly variable including airway narrowing, stridor, respiratory distress, recurrent respiratory tract infections, and pulmonary hypertension.

A rudimentary tag of skin often containing ear tissue including a core of cartilage and located just anterior to the auricle (outer part of the ear).