dilly vs mental case

dilly

noun

  • Someone or something that is remarkable or unusual. 

  • A dilly bag. 

adj

  • Silly; characteristic of a dill. 

  • Redolent of dill (the herb). 

mental case

noun

  • An insane person; a nutcase. 

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