abnormal vs thin on the ground

abnormal

adj
  • Of or pertaining to that which is irregular, in particular, behaviour that deviates from norms of social propriety or accepted standards of mental health. 

  • Not conforming to rule or system; deviating from the usual or normal type. 

noun
  • A person or object that is not normal. 

thin on the ground

adj
  • scarce, or difficult to find. 

How often have the words abnormal and thin on the ground occurred in a corpus of books? (source: Google Ngram Viewer )