A person who is devoted to books or book collecting; a bookworm or bibliophile.
From biblio- (book) + -otist (one who practices or specializes in), following patterns of -ist suffix words. This appears to be a learned coinage from 19th-century bibliographic scholarship.
While 'bibliophile' became the standard term, 'bibliotist' is a lesser-known variant that emphasizes the active practice or habit rather than just love—imagine calling someone not a 'book-lover' but a 'book-practitioner.'
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