three-ply vs three-way

three-ply

adj
  • Having three strands or layers 

noun
  • Yarn having three strands 

three-way

adj
  • Relating to three different directions. 

noun
  • Sexual activity involving three persons; a threesome; a ménage à trois. 

  • A serving of Cincinnati chili with spaghetti and cheese. 

How often have the words three-ply and three-way occurred in a corpus of books? (source: Google Ngram Viewer )