echinoderm
/ɪˈkaɪnəˌdɜrm/
noun
- A sea animal with a hard, spiny skin and a body that is usually divided into five parts, such as a starfish or sea urchin.
- Marine biologists study echinoderms to understand how they regenerate lost arms.
- An echinoderm like the sea urchin uses its spines to protect itself from predators.
- The starfish is a common echinoderm found in tide pools along the coast.