acrimonious vs mordant

acrimonious

adj
  • Angry, acid, and sharp in delivering argumentative replies: bitter, mean-spirited, sharp in language or tone. 

mordant

adj
  • Having or showing a sharp or critical quality 

  • Serving to fix a dye to a fibre. 

verb
  • To subject to the action of, or imbue with, a mordant. 

noun
  • A glutinous size used as a ground for gilding, to make the gold leaf adhere. 

  • Any substance used to facilitate the fixing of a dye to a fibre; usually a metallic compound which reacts with the dye using chelation. 

  • Any corrosive substance used in etching. 

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