opinionative vs rock-ribbed

opinionative

adj
  • Opinionated. 

  • Of, pertaining to, being, or expressing opinion. 

rock-ribbed

adj
  • Obstinately firm and unyielding in one's opinions 

  • Having rocky cliffs or outcroppings 

How often have the words opinionative and rock-ribbed occurred in a corpus of books? (source: Google Ngram Viewer )