appearance vs mask

appearance

noun
  • That which is not substance, essence, hypostasis; the outward reality as opposed to the underlying reality 

  • The act of appearing or coming into sight; the act of becoming visible to the eye. 

  • Chiefly used by nurses: the act of defecation by a patient. 

  • The act of appearing in a particular place, or in society, a company, or any proceedings; a coming before the public in a particular character. 

  • An instance of someone coming into a court of law to be part of a trial, either in person or represented by an attorney or such like; a court appearance 

  • A thing seen; a phenomenon; an apparition. 

  • The way something looks; personal presence 

  • Apparent likeness; the way which something or someone appears to others. 

mask

noun
  • That which disguises; a pretext or subterfuge. 

  • The mesh of a net; a net; net-bag. 

  • A cover, or partial cover, for the face, used for disguise or protection. 

  • A person wearing a mask. 

  • A pattern of bits used in bitwise operations; bitmask. 

  • A two-color (black and white) bitmap generated from an image, used to create transparency in the image. 

  • mesh 

  • The lower lip of the larva of a dragonfly, modified so as to form a prehensile organ. 

  • In a permanent fortification, a redoubt which protects the caponiere. 

  • A festive entertainment of dancing or other diversions, where all wear masks; a masquerade. 

  • Mash. 

  • The head of a fox, shown face-on and cut off immediately behind the ears. 

  • A social phenomenon where autistic people learn, practice, and perform certain behaviors and suppress others in order to appear more neurotypical. 

  • A flat covering used to block off an unwanted portion of a scene or image. 

  • A grotesque head or face, used to adorn keystones and other prominent parts, to spout water in fountains, and the like. 

  • A screen for a battery. 

verb
  • To set or unset (certain bits, or binary digits, within a value) by means of a bitmask. 

  • To bewilder; confuse. 

  • To conceal from view or knowledge; to cover; to hide. 

  • To conceal or disguise one's autism. 

  • To prepare tea in a teapot; alternative to brew. 

  • To disable (an interrupt, etc.) by setting or unsetting the associated bit. 

  • To cover (the face or something else), in order to conceal the identity or protect against injury; to cover with a mask or visor. 

  • To conceal; also, to intervene in the line of. 

  • (brewing) To mix malt with hot water to yield wort. 

  • To take part as a masker in a masquerade. 

  • to cover or shield a part of a design or picture in order to prevent reproduction or to safeguard the surface from the colors used when working with an air brush or painting 

  • To mash. 

  • To disguise as something else. 

  • To cover or keep in check. 

  • To wear a mask. 

  • To be infused or steeped. 

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