a book spine presenting a completely flat surface.
a book bound with such a spine.
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2024
How to use flat back in a sentence
She looked towards the open door and saw the footman's flat back, and narrow head covered with carefully plastered hair.December Love | Robert Hichens
The back is then "rounded" by use of a hammer; if the book is to be a "flat back" one, the rounding is very slight.The Building of a Book | Various
He was a splendid specimen of physical manhood, big and well-muscled, with a broad, flat back and soldierly carriage.The Pirate of Panama | William MacLeod Raine
Fig. 248 indicates the position of the hinge fixed so as to allow the door to open and lay flat back to the architrave moulding.Woodwork Joints | William Fairham
Its short waist suited her youthful bust and flat back and narrow shoulders.The Cup of Trembling and Other Stories | Mary Hallock Foote