boink vs horizontal polka

boink

noun
  • Sexual intercourse. 

  • A real-world social gathering of computer users. 

  • A sound of something hitting or bouncing off a surface, similar to plunk, but with more connotations of bounciness. 

verb
  • To hit or strike. 

  • To have sexual intercourse (with); to bonk. 

horizontal polka

noun
  • Sexual intercourse. 

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