8 letters · 18 points in Scrabble
noun a central cohesive source of support and stability
noun fortitude and determination
noun the series of vertebrae forming the axis of the skeleton and protecting the spinal cord
originFrom Middle English bakbon, bakebon, bac-bon; equivalent to back + bone. Compare the semantically analogous English ridgebone.
Etymology from Wiktionary, CC BY-SA 3.0