Glossary
Glossary of Terms for Collectors of Rare Maps, Atlases, Books, Globes and other related Scientific Objects.
J
Joint
The exterior flexible “hinge” where book cover meets book spine; “hinge” is usually used to designate the equivalent inside or interior flexible area. The joint is often an area that splits or cracks or otherwise shows wear in an older cloth or leather volume.
French: Charnière
German: Gelenk (außen)