book lung

1. 1.

   organ in many arachnids containing many thin folds of membrane resembling the leaves of a book

   Broaderrespiratory organ

Questions about book lung

What does book lung mean?

book lung means "organ in many arachnids containing many thin folds of membrane resembling the leaves of a book".

Is book lung a common word?

book lung is banded "Uncommon" — turns up in careful writing rather than conversation. The band comes from how often the word appears in a large corpus of everyday English, not from an editor's impression.