Refers to a book that is difficult to find, often used in bibliophile, antiquarian, or library contexts.
His hobby is collecting rare books.
This library holds many rare books.
絶版本 means 'out-of-print book', focusing on unavailability from the publisher, whereas 稀覯本 refers to rarity regardless of publication status.
Compound of 稀覯 (rare, scarce) + 本 (book). 稀覯 is itself a compound of 稀 (rare) and 覯 (to see, encounter), suggesting something rarely seen.