A person who believes that God created the universe and life forms, rejecting evolutionary explanations.
From 'creationism' plus '-ist' (Greek -istes, indicating a believer or practitioner). This agent noun formation follows standard English patterns for ideological adherents.
The term 'creationist' is relatively recent—it's almost never used before 1880—because before Darwin made evolution famous, nobody needed a special word for believing in creation since it was just the default religious view.
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