goblin vs ork

goblin

noun
  • One of various hostile supernatural creatures, now especially (fantasy literature) a malevolent and grotesque diminutive humanoid, often associated with orcs or trolls. 

ork

noun
  • A species of aggressive, fungal humanoid alien, corresponding to the orcs in other fantasy works. 

  • Alternate spelling of orc. 

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