environmentalist vs treehugger

environmentalist

adj
  • Of, or relating to environmentalism. 

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

  • 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. 

treehugger

noun
  • A species of libellulid dragonfly, Tyriobapta torrida, of Southeast Asia. 

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