big O vs opium

big O

noun
  • Orgasm. 

  • Upper bound function; see big O notation. 

opium

noun
  • Anything that numbs or stupefies. 

  • A yellow-brown, addictive narcotic drug obtained from the dried juice of unripe pods of the opium poppy, Papaver somniferum, and containing alkaloids such as morphine, codeine, and papaverine. 

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