racking vs unfrightening

racking

noun
  • spun yarn used in racking ropes 

  • A method of asphalt shingle application, whereby shingle courses are applied vertically, up the roof rather than laterally across and up. 

  • The process of clarifying, and thereby deterring further fermentation of, beer, wine or cider by draining or siphoning it from the dregs. 

unfrightening

adj
  • Not frightening. 

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