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.
The information shown above for breast is provided by Stedman's.
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