Starfish vs. Jellyfish — What's the Difference?

Starfish or sea stars are star-shaped echinoderms belonging to the class Asteroidea. Common usage frequently finds these names being also applied to ophiuroids, which are correctly referred to as brittle stars or basket stars.

Jellyfish and sea jellies are the informal common names given to the medusa-phase of certain gelatinous members of the subphylum Medusozoa, a major part of the phylum Cnidaria. Jellyfish are mainly free-swimming marine animals with umbrella-shaped bells and trailing tentacles, although a few are anchored to the seabed by stalks rather than being mobile.

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.

Any of numerous usually free-swimming marine cnidarians of the class Scyphozoa, characteristically having a gelatinous, tentacled, often bell-shaped medusa stage as the dominant phase of its life cycle. Also called true jellyfish.

Any of various marine echinoderms of the class Asteroidea, characteristically having a thick, often spiny body with five arms extending from a central disk. Also called asteroid, sea star.

Any of various similar or related cnidarians.

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.

(Informal) One who lacks force of character; a weakling.

(obsolete) Any many-armed or tentacled sea invertebrate, whether cnidarian, echinoderm, or cephalopod.

An almost transparent aquatic animal; any one of the acalephs, especially one of the larger species, having a jellylike appearance.

(slang) A woman (or, less commonly, a gay man) who reluctantly takes part in sexual intercourse, and lies on the back while spreading the limbs.

A cnidarian, a member of the phylum Cnidaria.

The anus. Category:en:Pornography

A ctenophore, a member of the phylum Ctenophora (the comb jellies).

(intransitive) To assume a splayed-out shape, like that of a starfish.

A sudoku technique involving possible cell locations for a digit, or pair, or triple, in uniquely four rows and four columns only. This allows for the elimination of candidates around the grid.

(transitive) To form into a splayed-out shape, like that of a starfish.

Any one of the acalephs, esp. one of the larger species, having a jellylike appearance. See Medusa and acaleph.

Any one of numerous species of echinoderms belonging to the class Asterioidea, in which the body is star-shaped and usually has five rays, though the number of rays varies from five to forty or more. The rays are often long, but are sometimes so short as to appear only as angles to the disklike body. Called also sea star, five-finger, and stellerid.

Large siphonophore having a bladderlike float and stinging tentacles

The dollar fish, or butterfish.

Any of numerous usually marine and free-swimming coelenterates that constitute the sexually reproductive forms of hydrozoans and scyphozoans

Echinoderms characterized by five arms extending from a central disk