lunatic vs sicko

lunatic

noun
  • An insane person. 

adj
  • Crazed, mad, insane, demented. 

sicko

noun
  • A mentally ill person. 

  • A person with unpleasant tastes, views or habits. 

  • A physically ill person. 

adj
  • Characterized by depraved tastes or habits; deviant. 

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