facial expression vs mug

facial expression

noun
  • The expression or countenance that seems to an onlooker to be represented by the appearance of a person or animals's face, resulting from specific use of that person's facial muscles. 

mug

noun
  • The face. 

  • A stupid or contemptible person. 

  • A gullible or easily-cheated person. 

  • A criminal. 

  • A large cup for beverages, usually having a handle and used without a saucer. 

  • Motherfucker (usually in similes, e.g. "like a mug" or "as a mug") 

adj
  • Uninteresting or unpleasant. 

verb
  • To assault for the purpose of robbery. 

  • To photograph for identification; to take a mug shot. 

  • To exaggerate a facial expression for communicative emphasis; to make a face, to pose, as for photographs or in a performance, in an exaggerated or affected manner. 

  • To learn or review a subject as much as possible in a short time; cram. 

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