ramification vs venation

ramification

noun
  • An arrangement of branches. 

  • A branching-out, the act or result of developing branches; specifically the divergence of the stem and limbs of a plant into smaller ones, or of similar developments in blood vessels, anatomical structures etc. 

  • An offshoot of a decision, fact etc.; a consequence or implication, especially one which complicates a situation. 

venation

noun
  • The arrangement of veins in a leaf, wing, or similar structure. 

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