doublure

[ duh-bloo r, doo-; French doo-blyr ]

/ dəˈblʊər, du-; French duˈblür /

an ornamental lining of a book cover.

Origin of doublure

1885–90; < French: a lining, equivalent to doubl(er) to line (literally, to double) + -ure -ure

Doublure, the inside face of the boards, especially applied to them when lined with leather and decorated.

Bookbinding, and the Care of Books |Douglas Cockerell
They occur near the anterior margin of the segment, and near the inner end of the doublure.

The Appendages, Anatomy, and Relationships of Trilobites |Percy Edward Raymond
It is also known that the epistoma is narrower and more firmly fused into the doublure in later than in earlier species.

The Appendages, Anatomy, and Relationships of Trilobites |Percy Edward Raymond
Since the front of the hypostoma is attached to this doublure, it stands high up within the vault and under the glabella.

The Appendages, Anatomy, and Relationships of Trilobites |Percy Edward Raymond

Width of doublure of front of cephalon on median line, 17 mm.; length of hypostoma, 20 mm.

The Appendages, Anatomy, and Relationships of Trilobites |Percy Edward Raymond

doublure

/ (dəˈblʊə, French dublyr) /

a decorative lining of vellum or leather, etc, on the inside of a book cover

C19: from French: lining, from Old French doubler to make double