polychromate vs skewbald

polychromate

adj

  • Composed of many colours 

noun

  • A salt or ion composed of multiple chromate groups 

skewbald

adj

  • Marked with patches of white and non-black colours. 

noun

  • A skewbald horse. 

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