colorful (US) / colourful vs polychromatic

colorful (US) / colourful

polychromatic

adj
  • Showing a variety, or a change, of colours; having many colours; multicoloured. 

  • Composed of more than one wavelength. 

How often have the words colorful (US) / colourful and polychromatic occurred in a corpus of books? (source: Google Ngram Viewer )