overly vs too

overly

adv
  • To an excessive degree. 

too

adv
  • To an excessive degree; over; more than enough. 

  • Used to contradict a negative assertion. 

  • Also; in addition. 

  • Likewise. 

  • To a high degree, very. 

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