disguise vs outward appearance

disguise

noun
  • The act or state of disguising, notably as a ploy. 

  • The appearance of something on the outside which masks what’s beneath. 

  • Material (such as clothing, makeup, a wig) used to alter one’s visual appearance in order to hide one's identity or assume another. 

verb
  • To change the appearance of (a person or thing) so as to hide, or to assume an identity. 

  • To avoid giving away or revealing (something secret); to hide by a false appearance. 

outward appearance

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