originate vs spearhead

originate

verb
  • To cause (someone or something) to be; to bring (someone or something) into existence; to produce or initiate a person or thing. 

  • To come into existence; to have origin or beginning; to spring, be derived (from, with). 

spearhead

verb
  • To drive or campaign ardently for, as an effort, project, etc. 

noun
  • The leading military unit in an attack. 

  • One who leads or initiates an activity (such as an attack or a campaign). 

  • The pointed head, or end, of a spear. 

  • A player who initiates attacking moves. 

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