butt-fucking vs fundament

butt-fucking

noun

  • anal sex 

adj

  • Engaging in anal sex 

fundament

noun

  • The bottom; the buttocks or anus. 

  • Foundation. 

  • The underlying basis or principle for a theoretical or mathematical system. 

How often have the words butt-fucking and fundament occurred in a corpus of books? (source: Google Ngram Viewer )