spines

/S P AY1 N Z/
noun
  1. 1

    The series of bones situated at the back from the head to the pelvis of a person, or from the head to the tail of an animal; backbone, vertebral column.

  2. 2

    Something resembling a backbone, such as a ridge, or a long, central structure from which other structures radiate.

  3. 3

    A pointed, fairly rigid protuberance or needle-like structure on an animal, shell, or plant.

  4. 4

    The heartwood of trees.

  5. 5

    Courage or assertiveness.

  6. 6

    The stiffness of an arrow.

Source: https://en.wiktionary.org/wiki/spine, https://en.wiktionary.org/wiki/spines