hoodlum vs keelie

hoodlum

noun
  • A rough or violent youth. 

  • A gangster; a hired thug. 

keelie

noun
  • A common or violent urban youth. 

  • A sparrowhawk or kestrel. 

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