Definitions for "Flat Back"
A book that is at right angles with the sides; opposed to the usual round back.
A hardcover binding where the spine is constructed with a board in it so that it appears "flat". Most standard 32 page children's' picture books have flatbacks. Budget Note: There is an up charge for flat backs with most printers. [Back
(square back): A book that has not been rounded and backed.
Keywords:  cope, wholly, drag, plane, mold
A pattern with a flat surface at the joint of the mold. It lies wholly within the drag or cope, and this joint of the mold is a plane surface. See Cope, Drag, Mold, Pattern.