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The lymphatic system is a network of tissues and organs that
help rid the body of toxins, waste and other unwanted materials. The primary
function of the lymphatic system is to transport lymph, a fluid containing
infection-fighting white blood cells, throughout the body. 

The lymphatic
system primarily consists of lymphatic vessels, which are similar to the
circulatory system's veins and capillaries. The vessels are connected to lymph
nodes, where the lymph is filtered. The tonsils, adenoids, spleen and thymus
are all part of the lymphatic system.

Lymph is a clear and colorless fluid; the word "lymph" comes from the Latin word lympha, which means "connected to water," 

Plasma leaves the body's cells once it has delivered its nutrients and removed debris. Most of this fluid returns to the venous circulation through tiny blood vessels called venules and continues as venous blood. The remainder becomes lymph