A person who compiles, edits, or contributes to an encyclopedia; an encyclopedia compiler or expert (American English spelling).
American English variant of encyclopaedian, dropping the 'a.' Both versions refer to professional encyclopedia workers and emerged during the great encyclopedia-publishing boom.
The most famous encyclopedian was probably Joseph-Nicolas Needham, a British scientist who spent 50+ years documenting the entire history of Chinese science—one person doing what we now need AI for.
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