A person who suffers from bibliomania; someone obsessed with collecting books, often to an extreme or unhealthy degree.
From bibliomania + -ac (Greek -akos, forming nouns for persons affected by a condition). Emerged alongside bibliomania in the 19th century as a clinical-sounding term for extreme book collectors.
Some famous bibliomaniacs, like collector Harry Elkins Widener, had personal libraries of over 3 million books—he was so obsessed he allegedly died trying to rescue rare books from the Titanic.
Complete word intelligence in one call. Free tier — 50 lookups/day.