heterobasionym vs metonymy

heterobasionym

noun
  • Synonym of synonym 

metonymy

noun
  • A metonym. 

  • The use of a single characteristic or part of an object, concept or phenomenon to identify the entire object, concept, phenomenon or a related object. 

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