overwhelm vs step on

overwhelm

verb
  • To engulf, surge over and submerge. 

  • To overpower emotionally. 

  • To cause to surround, to cover. 

  • To overpower, crush. 

noun
  • The state or condition of being overwhelmed. 

step on

verb
  • to adulterate a drug for the purpose of increasing its bulk, and therefore its profit; to dilute, cut. 

  • Used other than figuratively or idiomatically: see step, on. 

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