bichrome vs walleyed

bichrome

adj
  • Having two colours 

walleyed

adj
  • Having eyes of different colours. 

  • Suffering from exotropia. 

  • Having bulging eyes. 

  • Having eyes with a pale-coloured iris. 

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