charade vs smokescreen

charade

noun
  • A deception or pretense, originally an absurdly obvious one but now in general use. 

  • A single round of the game charades, an acted form of the earlier riddles. 

verb
  • To act out a charade (of); to gesture; to pretend. 

smokescreen

noun
  • Anything used metaphorically to conceal or distract. 

  • Smoke used as a disguise, mask or cover, as of troops in battle. 

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