coloring vs polychromasia

coloring

noun
  • A disguise or discoloration. 

  • The appearance as to color. 

  • Any substance used to give color. 

  • An assignment of a color to each vertex of a graph such that no two vertices connected by an edge are given the same color. 

  • An act or process which applies color. 

polychromasia

noun
  • A disorder in which there is an abnormally high number of red blood cells in the bloodstream as a result of their having been prematurely released from the bone marrow during blood formation. 

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