blindside vs fill in

blindside

verb
  • To attack (a person) on his or her blind side. 

  • To catch off guard; to take by surprise. 

noun
  • The blindside flanker, a position in rugby union, usually number 6. 

  • A person's weak point. 

  • A tram/train driver's field of blindness around a tram (trolley/streetcar) or a train; the side areas behind the tram/train driver. 

  • The space on the side of the pitch with the shorter distance between the breakdown/set piece and the touchline; compare openside. 

  • A driver's field of blindness around an automobile; the side areas behind the driver. 

fill in

verb
  • To beat up; to physically assault. 

  • To substitute for somebody or something. 

  • To complete a form or questionnaire with requested information. 

  • To fill; to replace material that is absent or has been removed. 

  • To inform somebody, especially to supply someone missing or missed information. 

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