donkey vs horseling

donkey

noun
  • A domestic animal, Equus asinus asinus, similar to a horse. 

  • A bad poker player. 

  • A fool. 

  • A small auxiliary engine. 

  • A stubborn person. 

horseling

noun
  • A young or little horse; foal; pony. 

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