n Any of various asteroids or other echinoderms (not in fact fish) with usually five arms, many of which eat bivalves or corals by everting their stomach.
n (vulgar|slang|usually in translations of Japanese pornography) an anus. See also chocolate starfish.
n (obsolete) Any many-armed or tentacled sea invertebrate, whether cnidarian, echinoderm, or cephalopod.