grass-roots vs intrinsic

grass-roots

intrinsic

noun
  • A built-in function that is implemented directly by the compiler, without any intermediate call to a library. 

  • An ability possessed by a character and not requiring any external equipment. 

adj
  • Built-in. 

  • Innate, inherent, inseparable from the thing itself, essential. 

  • Situated, produced, secreted in, or coming from inside an organ, tissue, muscle or member. 

How often have the words grass-roots and intrinsic occurred in a corpus of books? (source: Google Ngram Viewer )