pigeon breast /pij′ən/ [L, pipio, young bird; AS, broest, breast] , a congenital structural defect characterized by a prominent anterior projection of the xiphoid and the lower part of the sternum and by a lengthening of the costal cartilages. It may cause cardiorespiratory complications but rarely warrants surgical correction. Also called pectus carinatum, pigeon chest. −pigeon-breasted, adj.
