previous vs whilom

previous

adj
  • Prior; occurring before something else, either in time or order. 

  • Premature; acting or occurring too soon. 

noun
  • An existing criminal record (short for "previous convictions") 

  • A track record of similar behaviour. 

whilom

adj
  • At some time in the past; former, sometime. 

conj
  • During the same time that; while. 

  • Up to the time that; till, until. 

adv
  • At some time in the past; formerly, once upon a time. 

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