environmentalist vs guardian

environmentalist

noun
  • One who advocates for the protection of the environment and biosphere from misuse from human activity through such measures as ecosystem protection, waste reduction and pollution prevention. 

  • One who holds the view that environment, rather than heredity or culture, is the primary factor in the development of an individual or group. 

adj
  • Of, or relating to environmentalism. 

guardian

noun
  • Someone who guards, watches over, or protects. 

  • A superior in a Franciscan monastery. 

  • A person legally responsible for a minor (in loco parentis). 

  • A person legally responsible for an incompetent person. 

  • A major or final enemy; boss. 

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