An organ that is part of the lymphatic system, in which T lymphocytes grow and multiply. The thymus is in the chest behind the breastbone.
Source: NCI Dictionary of Cancer Terms
Caption: Anatomy of the thymus gland. The thymus gland is a small organ that lies in the upper chest under the breastbone. It makes white blood cells, called lymphocytes, which protect the body against infections.Date last modified: 2012-05-24