infirm vs lusty

infirm

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

adj
  • Weak or ill, not in good health. 

  • Irresolute; weak of mind or will. 

  • Frail; unstable; insecure. 

lusty

adj
  • Hearty, merry, gleesome, enthusiastic, lively, stirring. 

  • Exhibiting lust (in the obsolete sense meaning "vigor"); strong, healthy, robust; vigorous; full of sap or vitality. 

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