noun (n)

• the peeling off in flakes or scales of bark or dead skin(noun.phenomenon)

  Example:
  Exfoliation is increased by sunburn.
  

  source: wordnet30
• a thin flake of dead epidermis shed from the surface of the skin(noun.object)

  Synonym:
  scale, scurf
  

  source: wordnet30
• The scaling off of a bone, a rock, or a mineral, etc.; the state of being exfoliated.(noun)

  source: webster1913