convoluted vs tortuous

convoluted

adj
  • Having numerous overlapping coils or folds; convolute. 

  • Complex, complicated, or intricate. 

tortuous

adj
  • Twisted; having many turns; convoluted. 

  • Oblique; applied to the six signs of the zodiac (from Capricorn to Gemini) that ascend most rapidly and obliquely. 

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