concentration vs dullness

concentration

noun
  • The proportion of a substance in a whole. 

  • The act, process or product of reducing the volume of a liquid, as by evaporation. 

  • The act or process of removing the dress of ore and of reducing the valuable part to smaller compass, as by currents of air or water. 

  • The direction of attention to a specific object. 

  • A field or course of study on which one focuses, especially as a student in a college or university. 

  • The amount of solute in a solution measured in suitable units (e.g., parts per million (ppm)) 

  • The matching game pelmanism. 

dullness

noun
  • The quality of not perceiving or kenning things distinctly. 

  • The quality of being uninteresting; boring; humorless or irksome. 

  • The quality of being slow of understanding things; stupidity. 

  • Lack of interest or excitement. 

  • The lack of visual brilliance; want of sheen. 

  • bluntness. 

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