The phrase "left spine" refers to the pages on the left side of a book or document when it is opened. It is the part that is closest to the binding or spine. Full definition
Both books are bound with a blue linen hardcover, stamped gold - leaf spine text, cream paper, and full - color dust - jacket cover with a gloss finish. (scottsemegran.com)
Eventually, there should be a smoothness and softness to it that leaves the spine undisturbed and the nervous system quiet. (vikasayoga.com)
The cauda equina are the nerve roots leaving the spine. (ashgi.org)