colourable vs skewbald

colourable

adj
  • That can be coloured. 

  • Apparently true; specious; potentially justifiable. 

skewbald

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

noun
  • A skewbald horse. 

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