environmentalist vs environmentalism

environmentalist and environmentalism both are nouns.

Word	Noun	Adjective	Verb	Adverb
environmentalist	Yes	No	No	No
environmentalism	Yes	No	No	No

environmentalist (noun)	environmentalism (noun)
someone who works to protect the environment from destruction or pollution	the activity of protecting the environment from pollution or destruction
	the philosophical doctrine that environment is more important than heredity in determining intellectual growth