infirm vs powerless

infirm

adj
  • Frail; unstable; insecure. 

  • Weak or ill, not in good health. 

  • Irresolute; weak of mind or will. 

verb
  • To contradict, to provide proof that something is not. 

powerless

adj
  • Lacking sufficient power or strength. 

  • Lacking legal authority. 

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