barfly vs pisshead

barfly

noun
  • a person who spends much time in a bar or similar drinking establishment 

  • a promiscuous person, especially a woman, who frequents bars hoping to find sexual partners 

pisshead

noun
  • A person who regularly overindulges in alcoholic drink. 

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