loon vs wing nut

loon

noun
  • A crazy or deranged person; a lunatic. 

  • A boy, a lad. 

  • Any of various birds, of the order Gaviiformes, of North America and Europe that dive for fish and have a short tail, webbed feet and a yodeling cry. 

  • An English soldier of an expeditionary army in Ireland. 

  • A simpleton. 

  • A harlot; mistress. 

wing nut

noun
  • One who advocates extreme measures or changes, especially if they hold or are perceived to hold far-right viewpoints; a radical or reactionary. 

  • A nut with wing-like projections to provide leverage in turning with thumb and forefinger. 

  • Someone with large, protruding ears. 

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