deficient vs unfitness

deficient

noun
  • A person who is deficient. 

adj
  • Insufficient or inadequate in amount. 

  • Lacking something essential; often construed with in. 

  • Of a number n, Having the sum of divisors σ(n)<2n, or, equivalently, the sum of proper divisors (or aliquot sum) s(n). 

unfitness

noun
  • The characteristic of being unfit or ill-suited. 

  • The characteristic of being unfit or out of physical shape. 

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