ecologist vs environmentalist

ecologist

noun
  • An environmentalist (one who advocates for the protection of the environment). 

  • A scholar of ecology. 

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. 

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