Collectivist
Part of speech: noun
Definition: an advocate of collectivism
Part of speech: adjective
Definition: of or pertaining to collectivism
Socialistic
Part of speech: adjective
Definition: Of or relating to socialism.
Collectivist as an adjective is of or pertaining to collectivism while Socialistic as an adjective is of or relating to socialism.
Part of speech: noun
Definition: an advocate of collectivism
Part of speech: adjective
Definition: of or pertaining to collectivism
Part of speech: adjective
Definition: Of or relating to socialism.
We hope you now know whether to use Collectivist or Socialistic in your sentence.