• A clinical finding in which there is depression of the sternum visible on examination of the chest. (ACC-AHA)
  NCI
  U.S. National Cancer Institute, 2021
• A defect of the chest wall characterized by a depression of the sternum, giving the chest (pectus") a caved-in ("excavatum") appearance." [https://orcid.org/0000-0002-0736-9199]
  Human Phenotype Ontology (HPO)
  The Human Phenotype Ontology Project, 2025
• Pectus excavatum, also known as sunken or funnel chest, is a congenital chest wall deformity in which several ribs and the sternum grow abnormally, producing a concave, or caved-in, appearance in the anterior chest wall. The image below illustrates the typical appearance of this deformity in a 16-year-old boy.
  Medscape
  WebMD, 2025
• Pectus excavatum is a condition in which a person's breastbone is sunken into his or her chest. In severe cases, pectus excavatum can look as if the center of the chest has been scooped out, leaving a deep dent.
  Mayo Clinic
  Mayo Foundation for Medical Education and Research, 2025
• Pectus excavatum, a chest deformity caused by depression of the breastbone, or sternum. Pectus excavatum is generally not noticeable at birth but becomes more evident with age unless surgically corrected. In most instances the abnormality is due to a shortened central tendon of the diaphragm, the...
  Encyclopedia Britannica
  Encyclopedia Britannica, Inc., 2025