exocarp vs orange peel

exocarp

noun
  • The outermost layer of the pericarp of fruits; the skin or epicarp 

orange peel

noun
  • The skin of an orange, including the pith. 

  • A color between orange and amber, like that of an orange peel. 

  • An uneven surface resembling orange peel, especially cellulite or an imperfect finish on a spray-painted object such as a car. 

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