A follower or supporter of acephalism, or alternatively, a prehistoric creature without a distinct head.
From 'acephal-' (without head) + '-ite' (suffix indicating a follower or a type of organism). The suffix '-ite' has dual meanings in English: both ideology followers and biological specimens.
The term 'acephalite' beautifully blurs scientific and political language—you could use it for both a headless worm fossil and a person rejecting hierarchical authority, showing how the same Greek roots describe nature and human society.
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