A marine echinoderm (invertebrate) with five or more radiating arms. The undersides of the arms bear tube feet for locomotion and, in predatory species, for opening the shells of molluscs.
- ‘Growth on the hull of the wreck consists largely of small shells with grazing sea urchins and starfish.’
- ‘Scattered on the cloth are pinecones and seashells, a sand dollar, a starfish, a sea urchin.’
- ‘Echinoderms include the sea urchins and starfish.’
- ‘Thus far there are no serious signs of predation by crabs or starfish.’
- ‘Sea urchins and starfish are the last and most obvious group of marine creatures lurking to catch unwary and clumsy humans.’