Lymph node

A Lymph node () is an organ consisting of many types of cells, and is a part of the lymphatic system. Lymph nodes are found all through the body, and remove foreign ("not of the body") objects from the body. Lymph nodes contain white blood cells. They are important for the correct use of the immune system.
Where They Are Found.
In the human body, the most likely place where lymph nodes can be felt are the neck, underarms, and groin area.