monochrome vs monochromous

monochrome

adj
  • Representing colours with shades of gray. 

  • Having only one colour. 

noun
  • A ceramic glaze of a single colour; an object so glazed. 

  • A black and white image, especially such a photograph. 

monochromous

adj
  • Synonym of monochrome 

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