spiculum
/ˈspɪkjələm/
noun
- A small, sharp, needle-like structure or spine, especially on an animal or plant.
- The sea urchin's spiculum can break off and remain in the skin.
- The caterpillar's body was covered in a fine spiculum that irritated predators.
- Under the microscope, the sponge's spiculum looked like a tiny glass needle.