idiomatic vs polyword

idiomatic

noun
  • Synonym of idiom 

adj
  • Pertaining or conforming to idiom, the natural mode of expression of a language. 

  • Resembling or characteristic of an idiom. 

  • Relating to parts or pieces which are written both within the natural physical limitations of the instrument and human body and, less so or less often, the styles of playing used on specific instruments. 

polyword

noun
  • A phrase that acts like a single word. 

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