dualistic vs twosome

dualistic

adj
  • Of or relating to dualism. 

twosome

adj
  • Being or constituting a pair; two. 

  • Performed by two individuals. 

  • Twofold; double. 

noun
  • A group of two; a pair; a couple; a group of two distinct individuals or components. 

  • A dance for two people. 

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