loon vs squarehead

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. 

squarehead

noun
  • A socially conventional or boring person. 

  • A foreigner of Germanic origin, especially a German, Dutch, or Scandinavian person. 

  • An honest person; a non-criminal. 

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