Darwinism vs evolutionism

Darwinism and evolutionism both are nouns.

Word	Noun	Adjective	Verb	Adverb
Darwinism	Yes	No	No	No
evolutionism	Yes	No	No	No

As nouns, evolutionism is a hypernym of Darwinism; that is, evolutionism is a word with a broader meaning than Darwinism:

Darwinism: a theory of organic evolution claiming that new species arise and are perpetuated by natural selection
evolutionism: (biology) a scientific theory of the origin of species of plants and animals

Other hypernyms of Darwinism include theory of evolution, theory of organic evolution.

Darwinism (noun)	evolutionism (noun)
a theory of organic evolution claiming that new species arise and are perpetuated by natural selection	(biology) a scientific theory of the origin of species of plants and animals