turtleback

• turtle-back

turtle +‎ back

turtleback (plural turtlebacks)

1. Anything having the shape of a turtle's back (that is, its shell).
   • Poul Anderson, The Winter of the World

     Up he went on concrete stairs that were eroded to turtlebacks and slippery with evening's frost […]

2. (nautical) A convex deck at the bow or stern of a vessel, designed to shed seawater quickly.
3. A primitive stone celt of a form suggesting the back of a turtle.
4. A library binding of a mass market paperback with a generic hardcover.

   (The addition of quotations indicative of this usage is being sought):

   • 1995, The Georgia Librarian (volumes 32-34)

     When you order Turtleback Books from Baker & Taylor, you can be assured you get Turtlebacks!

5. Any plant of the genus Psathyrotes of annual and perennial forbs and low subshrubs native to dry areas of southwestern North America.

• turtle-backed
• turtle-back scale