A person who believes in or practices depredation; one who supports plundering or preying upon others; an advocate of systematic theft.
From depredation plus -ist suffix (meaning 'one who practices or believes in'), creating a noun for someone actively engaged in or supporting plundering.
The term 'depredationist' rarely appears in modern English because we now use words like 'pirate,' 'warlord,' or 'criminal'—but it survives in academic writing about historical raids and colonial exploitation.
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