hooligan vs roughneck

hooligan

noun
  • A person who causes trouble or violence. 

  • A type of fish, an anadromous smelt, Thaleichthys pacificus, found in the North Pacific. 

  • A member of the coast guard. 

roughneck

noun
  • Someone with rough manners; a rowdy or uncouth person. 

  • An ironworker; a dirty or low-paid worker, a labourer. 

  • A labourer on an oil rig. 

verb
  • To work as a laborer on an oil rig. 

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