crackpot vs odd fish

crackpot

noun
  • An eccentric, crazy or foolish person. 

  • Someone addicted to crack cocaine (i.e. a drug addict). 

adj
  • Eccentric or impractical. 

odd fish

noun
  • An unusual thing or eccentric person. 

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