red sorrel vs roan

red sorrel

noun
  • The plant roselle (Hibiscus sabdariffa). 

  • Rumex acetosella 

roan

noun
  • The color of such an animal. 

  • A kind of leather used for slippers, bookbinding, etc., made from sheepskin, tanned with sumac and colored to imitate ungrained morocco. 

  • An animal such as a horse that has a coat of a dark base color with individual white hairs mixed in. 

adj
  • Especially of a horse, having a coat of a dark base color with individual white hairs mixed in 

  • Made of the leather called roan. 

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