noun (n)

• one who lives in solitude(noun.person)

  Synonym:
  hermit, recluse, solitary, solitudinarian
  

  source: wordnet30
• someone who lives in a cave(noun.person)

  Synonym:
  cave dweller, cave man, caveman
  

  source: wordnet30
• One of any savage race that dwells in caves, instead of constructing dwellings; a cave dweller. Most of the primitive races of man were troglodytes.(noun)

  source: webster1913