fabricate vs superstruct

fabricate

verb
  • To form into a whole by uniting its parts; to construct; to build. 

  • To form by art and labor; to manufacture; to produce. 

  • To invent and form; to forge; to devise falsely. 

  • To cut up an animal as preparation for cooking, particularly used in reference to fowl. 

superstruct

verb
  • To build over or upon (another structure); to erect upon (a foundation). 

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