jellyfish

/ˌdʒɛliˈfɪʃ/

/ˈdʒelifɪʃ/

Other forms: jellyfishes

A jellyfish is a marine animal with long tentacles that hang down from a bell-shaped body. Many jellyfish are nearly transparent.

Jellyfish may look like they're made of jelly, but their bodies are actually 95 percent water. These umbrella-shaped creatures look graceful floating in the water, but they collapse into a flat blob on land. Jellyfish don't have organs, just a simple nervous system and three layers including the elastic, jelly-like mesoglea that gives them their name. In the 19th century, it became fairly common to call a weak person a jellyfish, a figurative usage that's still around today.

Definitions of jellyfish

1. noun

   large siphonophore having a bladderlike float and stinging tentacles
   synonyms: Portuguese man-of-war, man-of-war

   type of:

   siphonophore

   a floating or swimming oceanic colony of polyps often transparent or showily colored
2. noun

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

   Aegina

   small medusa

   Chrysaora quinquecirrha

   a type of jellyfish

   type of:

   cnidarian, coelenterate

   radially symmetrical animals having saclike bodies with only one opening and tentacles with stinging structures; they occur in polyp and medusa forms