gray-haired vs hoar

gray-haired

hoar

noun

  • A white or greyish-white colour. 

  • Hoariness; antiquity. 

adj

  • Hoarily bearded. 

  • Of a white or greyish-white colour. 

How often have the words gray-haired and hoar occurred in a corpus of books? (source: Google Ngram Viewer )