deficient vs impaired

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). 

noun
  • A person who is deficient. 

impaired

adj
  • Rendered less effective. 

  • inebriated, drunk. 

noun
  • A criminal charge for driving a vehicle while impaired. 

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