idiot savant vs savant

idiot savant

noun
  • A person who exhibits an extraordinary ability in one subject (often mathematics) whilst being intellectually disabled in many other domains. 

savant

noun
  • A person with significant mental disabilities who is very gifted in one area of activity, such as playing the piano or mental arithmetic. 

  • A person of learning, especially one who is versed in literature or science. 

  • A person who is considered eminent because of their achievements. 

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