gland vs lymphatic system

gland

noun
  • A structure resembling a gland, especially a lymph node. 

  • A gland used around a tap, valve or faucet. 

  • A gland used around a ship’s propeller shaft. 

  • A specialized cell, group of cells, or organ of endothelial origin in the human or animal body that synthesizes a chemical substance, such as hormones or breast milk, and releases it, often into the bloodstream (endocrine gland) or into cavities inside the body or its outer surface (exocrine gland). 

  • A secretory structure on the surface of an organ. 

lymphatic system

noun
  • In mammals, including humans, a network of lymph vessels and lymph nodes that transport fluid, fats, proteins, and lymphocytes to the bloodstream as lymph, and remove microorganisms and other debris from tissues. 

How often have the words gland and lymphatic system occurred in a corpus of books? (source: Google Ngram Viewer )