therefor vs what for

therefor

adv

  • For that; in return for that. 

  • Coordinate terms: herefor, wherefor 

what for

adv

  • For what purpose. 

  • For what reason; why. 

noun

  • An unspecified punishment or rebuke 

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