fig leaf vs illusion

fig leaf

noun
  • Anything used to conceal something undesirable or that one does not want to be discovered. 

  • A leaf of the fig plant. 

  • A representation of leaf of a fig plant used to cover the genitals of a nude figure in a work of art (alluding to Genesis iii 7, in which Adam and Eve use fig leaves to hide their nakedness). 

illusion

noun
  • Anything that seems to be something that it is not. 

  • A misapprehension; a belief in something that is in fact not true. 

  • A magician’s trick. 

  • The state of being deceived or misled. 

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