ear to the ground vs rational

ear to the ground

noun
  • The practice or characteristic of carefully gathering information; a state or mindset of attentiveness. 

  • Pursuing the practice or having the characteristic of carefully gathering information; well-informed. 

rational

noun
  • A rational number: a number that can be expressed as the quotient of two integers. 

  • The breastplate worn by Israelite high priests. 

adj
  • Healthy or balanced intellectually; exhibiting reasonableness. 

  • Logically sound; not self-contradictory or otherwise absurd. 

  • Of an algebraic expression, capable of being expressed as the ratio of two polynomials. 

  • Expressing the type, structure, relations, and reactions of a compound; graphic; said of formulae. 

  • Of a number, capable of being expressed as the ratio of two integers. 

  • Expressing a physical object. 

  • Capable of reasoning. 

How often have the words ear to the ground and rational occurred in a corpus of books? (source: Google Ngram Viewer )