1a series of vertebrae extending from the skull to the small of the back, enclosing the spinal cord and providing support for the thorax and abdomen; the backbone.
a thing’s central feature or main source of strength:players who will form the spine of our team
resolution or strength of character.
the part of a book’s jacket or cover that encloses the inner edges of the pages, facing outward when the book is on a shelf and typically bearing the title and the author’s name.
2 Zoology & Botany any hard pointed defensive projection or structure, such as a prickle of a hedgehog, a spikelike projection on a sea urchin, a sharp ray in a fish’s fin, or a spike on the stem of a plant.
Geology a tall mass of viscous lava extruded from a volcano.
[in combination]:broken-spined paperbacks
late Middle English: shortening of Old French espine, or from Latin spina 'thorn, prickle, backbone'