book lung book lover • book machine · · · Info · Definitions · Characters · · book lung · · Text Common · · Latin · · Scripts 9 · · Length 2 · · Syllables Definitions · · · (noun) organ in many arachnids containing many thin folds of membrane resembling the leaves of a book. Synonyms: book lung. · · Noun Definition 1 Characters · · space U+0020 b latin small letter b U+0062 g latin small letter g U+0067 k latin small letter k U+006B l latin small letter l U+006C n latin small letter n U+006E o latin small letter o U+006F u latin small letter u U+0075