1. The pectoral surface of the thorax.
2. The female organ of milk secretion; one of two commonly hemispheric projections anterior to the pectoral muscles including the mammary glands within a highly variable amount of fat in the subcutaneous tissue and bearing the nipple superficially on either side of the chest of the mature female; it is rudimentary in the male.
Stedman’s Medical Dictionary © Wolters Kluwer Health. All rights reserved.