come clean vs sham

come clean

verb
  • 1921, B. M. Bower, chapter 6, in Sawtooth Ranch 

  • To confess; admit the truth. 

  • 1977 Oct. 23, John Gardner, "The World Of Tolkien," New York Times (retrieved 12 Sept 2013) 

  • 2005 August 8, "Quotes of the Day," Time (retrieved 12 Sept 2013) 

sham

noun
  • A decorative cover for a pillow. 

  • A false front, or removable ornamental covering. 

  • Trickery, hoaxing. 

  • A fake; an imitation that purports to be genuine. 

  • Champagne. 

verb
  • To obtrude by fraud or imposition. 

  • To deceive, cheat, lie. 

  • To assume the manner and character of; to imitate; to ape; to feign. 

adj
  • mock 

  • Intended to deceive; false. 

  • counterfeit; unreal 

  • See also Thesaurus:fake 

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