sugar apple vs sweetsop

sugar apple

noun
  • Sweetsop, Annona squamosa, a West Indian tree or its fruit. 

sweetsop

noun
  • The sugar apple, Annona squamosa. 

  • The tropical American evergreen tree on which it grows. 

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