rachis
/ˈreɪkɪs/
noun
- The main axis or central shaft of a feather, leaf, or compound structure.
- The rachis of a feather runs down the center, supporting the barbs.
- The bird's broken rachis made it unable to fly properly.
- In ferns, the rachis is the central stem of the frond.
- The spinal column or backbone.
- Injuries to the rachis can cause paralysis.
- The rachis protects the spinal cord in vertebrates.
- The skeleton's rachis was curved due to scoliosis.