A person who engages in feuds or advocates for feuding; alternatively, a scholar who studies feuds or feudalism.
From feud plus -ist suffix meaning 'one who practices or studies.' This term can describe both feuding participants and academic specialists, making it somewhat ambiguous.
A feudist could be a medieval nobleman locked in blood-feuds with rival clans, or a modern historian studying how feuds functioned in medieval society—the word captures both the practice and its study.
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