duffer vs harebrain

duffer

noun
  • An incompetent, indolent, or clumsy person. 

  • Any of various nymphalid butterflies of the genus Discophora. 

  • A player having little skill, especially a golfer who duffs. 

  • A racing pigeon that does not perform well. 

  • A cow that does not produce milk. 

harebrain

noun
  • A person who lacks good sense; One who is foolish and reckless. 

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