atypical vs subnormal

atypical

adj
  • Unusual or irregular. 

  • Not conforming to the normal type. 

noun
  • An atypical antipsychotic. 

subnormal

adj
  • denormal 

  • Less than normal. 

noun
  • A person whose abilities are less than normal. 

  • That part of the axis of a curved line which is intercepted between the ordinate and the normal. 

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