peninsula vs subcontinent

peninsula

noun
  • A piece of land projecting into water from a larger land mass. 

subcontinent

noun
  • A large landmass which is either smaller than a continent (such as Greenland), or part of an even larger continent (such as the Indian subcontinent). 

name
  • The Indian subcontinent, South Asia. 

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