A person who believes in and advocates for antihierarchism, opposing hierarchical structures and supporting more equal forms of organization.
From antihierarchism + -ist (suffix for a person who practices or believes in something). This creates a noun describing an adherent of antihierarchic philosophy.
An antihierarchist might be a programmer in an open-source community, a labor union organizer, or even a parent trying to make family decisions collaboratively rather than 'because I said so!'
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