The chief or highest-ranking druid in Celtic religion or historical/fantasy fiction.
From 'arch-' (chief, principal) and 'druid' (from Celtic religious leaders), possibly from Gaulish 'druides.' This term has been used since the 18th century in historical and antiquarian works discussing Celtic religion.
Most 'archdruids' in modern fantasy come from Romantic-era scholars who were inventing Celtic religion while 'restoring' it—the term shows how enthusiastic Victorians created hierarchical versions of ancient religions that probably never existed that way.
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