cloak vs hinterland

cloak

noun
  • That which conceals; a disguise or pretext. 

  • A long outer garment worn over the shoulders covering the back; a cape, often with a hood. 

  • A blanket-like covering, often metaphorical. 

  • A text replacement for an IRC user's hostname or IP address, making the user less identifiable. 

verb
  • To cover up, hide or conceal. 

  • To render or become invisible via futuristic technology. 

  • To cover as with a cloak. 

hinterland

noun
  • That which is unknown or unexplored about someone. 

  • The land immediately next to, and inland from, a coast. 

  • A remote or undeveloped area, a backwater. 

  • Anything vague or ill-defined, especially something that is ill understood. 

  • The rural territory surrounding an urban area, especially a port. 

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