longbeard vs old fart

longbeard

noun
  • Synonym of greybeard (“an old man”) 

  • A man with a long beard. 

  • Synonym of greybeard (“experienced long-time member of a group”) 

  • Synonym of greybeard (“a bellarmine”) 

old fart

noun
  • An elderly person who holds old-fashioned views. 

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