gelt vs slough shark

gelt

noun
  • A gelding. 

  • Tribute; tax. 

  • A lunatic. 

  • Chocolate candy in the shape of coins, usually wrapped in metallic foil, usually eaten on Hanukkah and often used for games of dreidel. 

  • Money, especially that given as a gift on Hanukkah or used in games of dreidel. 

  • Money. 

slough shark

noun
  • northern pike 

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