A person who believes in or practices adiaphorism; someone who holds that certain matters are morally indifferent.
From 'adiaphorism' plus the agent suffix '-ist,' which creates a noun for someone who practices or believes in the system named by the root word.
An adiaphorist was seen as dangerously relaxed about morality by strict religious folk, but moderate adiaphorists were actually trying to prevent scrupulosity—the exhausting obsession with tiny moral details—by saying some things are genuinely neutral.
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