atypical vs unthought-of

atypical

adj

  • Unusual or irregular. 

  • Not conforming to the normal type. 

noun

  • An atypical antipsychotic. 

unthought-of

adj

  • unexpected 

  • unimagined 

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