A person who is obsessed with collecting books and possessing rare editions, often to the point of irrational or unhealthy behavior.
From 'bibliomania' plus '-ist' suffix denoting a person who practices or believes in something. It specifically identifies someone whose book passion has become a defining obsession.
Bibliomanists actually get documented in medical literature as examples of compulsive behavior—yet their passion has led to the creation of some of the world's greatest private libraries!
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