impression vs speculative fiction

impression

noun
  • A print on paper from a wood block, metal plate, etc. 

  • set of copies of a publication printed at one time having the same content, layout, pagination, etc. 

  • The vivid perception of something as it is experienced, in contrast to ideas or thoughts drawn from memory or the imagination. 

  • The indentation or depression made by the pressure of one object on or into another. 

  • An online advertising performance metric representing an instance where an ad is shown once. 

  • A vague recalling of an event, a belief. 

  • An outward appearance. 

  • An impersonation, an imitation of the mannerisms of another individual. 

  • The first coat of colour, such as the priming in house-painting etc. 

  • The overall effect of something, e.g., on a person. 

verb
  • To manipulate a blank key within a lock so as to mark it with impressions of the shape of the lock, which facilitates creation of a duplicate key. 

speculative fiction

noun
  • A particular work belonging to this class. 

  • A class of fiction involving fantastic, supernatural or futuristic elements, including fantasy, horror, and science fiction, dealing with worlds, themes, and characters not part of everyday life. 

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