• A system of channels that drains excess clear fluid, called lymph, from tissues and returns it into the bloodstream.
  Harvard Dictionary of Health Terms
  Harvard Medical Publishing, 2011
• A system of organs and tissues that process and transport immune cells and LYMPH.
  NLM Medical Subject Headings
  U.S. National Library of Medicine, 2025
• Segment of lymphoid system which has as its direct parts right lymphatic tree organ and thoracic duct tree. Examples: There is only one lymphatic system.
  Foundational Model of Anatomy
  University of Washington, 2017
• System of organs and tissues that process and transport immune cells and lymph.
  CRISP Thesaurus
  National Institutes of Health, 2006
• The anatomic system that includes the lymph nodes, lymphoid tissues in various organs (spleen, thymus, tonsils, gastrointestinal tract), and lymphatic vessels. It is part of the immune system that offers protection against infections.
  NCI
  U.S. National Cancer Institute, 2021
• The tissues and organs that produce, store, and carry white blood cells that fight infections and other diseases. This system includes the bone marrow, spleen, thymus, lymph nodes, and lymphatic vessels (a network of thin tubes that carry lymph and white blood cells). Lymphatic vessels branch, like blood vessels, into all the tissues of the body.
  NCI Dictionary of Cancer Terms
  U.S. National Cancer Institute, 2021
• Plasma, along with some white blood cells, routinely moves out of capillaries into the interstitial space. Most of the fluid and its constituents is taken up by tissue cells or reabsorbed into the vascular tree, depending on the balance of hydrostatic and oncotic pressures. However, some of the fluid, along with certain cells and...
  Merck Manuals
  Merck & Co., Inc., 2025
• The lymphatic system parallels the cardiovascular system (see the images below). The lymphatic system is unique, in that it is a 1-way system that returns lymph fluid via vessels to the cardiovascular system for eventual elimination of toxic byproducts by end organs, such as the kidney, liver, colon, skin, and lungs.
  Medscape
  WebMD, 2025
• Lymphatic system, a subsystem of the circulatory system in the vertebrate body that consists of a complex network of vessels, tissues, and organs. The lymphatic system helps maintain fluid balance in the body by collecting excess fluid and particulate matter from tissues and depositing them in the...
  Encyclopedia Britannica
  Encyclopedia Britannica, Inc., 2025