A person who writes for, edits, or compiles a cyclopedia or encyclopedia.
From 'cyclopedia' plus the agent suffix '-ist,' meaning 'one who practices or specializes in.' This term emerged when cyclopedias were being actively compiled in the 17th-18th centuries.
A cyclopedist was a type of intellectual superstar—they had to be knowledgeable enough to write accurately about hundreds of different topics, so they were walking libraries of knowledge!
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