jellyfish

noun

jel·​ly·​fish ˈje-lē-ˌfish How to pronounce jellyfish (audio)
1
a
: the typically free-swimming, bell-shaped, usually sexually-reproducing solitary or colonial form of a cnidarian in which the whorls of tentacles lined with nematocysts arise and hang down from the margin of the nearly transparent, gelatinous bell : medusa
especially : a large medusa characteristic of the siphonophores and scyphozoans (such as the sea nettle or box jellyfish)
2
: a person lacking backbone or firmness

Illustration of jellyfish

Illustration of jellyfish
  • jellyfish 1a

Examples of jellyfish in a Sentence

a jellyfish who was afraid to tell her boss that her latest brainstorm was just plain bad
Recent Examples on the Web Food Does this new robot-staffed chocolate emporium signal a themed restaurant comeback? March 2, 2023 Expansive screens surround the diners — an underwater scene of colorful jellyfish accompanies a seafood pairing. Todd Martens, Los Angeles Times, 20 Mar. 2024 In 1931, prolific scientist-director Jean Painlevé shot eight delightful, surrealist short films underwater, capturing phenomena both scary and sensual, including the birth of jellyfish and the mating rituals of octopi. Carolina Dalia Gonzalez, Vogue, 4 Mar. 2024 Unlike true jellyfish, comb jellies glide through the water, propelled by rows of fused, hair-like cilia called combs. Anna Nordseth, Discover Magazine, 1 Mar. 2024 Scientists have discovered that various deep-sea creatures, including fish, squid and jellyfish, use specific patterns of light emission as part of their mating rituals. Scott Travers, Forbes, 28 Feb. 2024 Recreate the jellyfish’s transparency through the use of floaty fabrics. Maggie Gillette, Better Homes & Gardens, 11 Feb. 2024 The aquarium features a wide variety of marine life, from water-dwellers like sharks, jellyfish and dolphins to ocean-adjacent species like puffins, turtles and monitor lizards. Natalie Wallington, Kansas City Star, 23 Jan. 2024 The netted surroundings also protect swimmers from currents and jellyfish. Gemma Harris, Robb Report, 8 Mar. 2024 Among the creatures that are less negatively impacted by warming waters include squid, octopus and jellyfish, which is most commonly consumed today in China and Vietnam. Mary Whitfill Roeloffs, Forbes, 1 Mar. 2024

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'jellyfish.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History

First Known Use

1818, in the meaning defined at sense 1a

Time Traveler
The first known use of jellyfish was in 1818

Dictionary Entries Near jellyfish

Cite this Entry

“Jellyfish.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/jellyfish. Accessed 28 Mar. 2024.

Kids Definition

jellyfish

noun
jel·​ly·​fish ˈjel-ē-ˌfish How to pronounce jellyfish (audio)
1
: any of numerous free-swimming coelenterate animals that reproduce sexually and have a jellylike, saucer-shaped, and usually nearly transparent body and tentacles with stinging cells
2
: any of various sea animals that resemble a jellyfish

Medical Definition

jellyfish

noun
jel·​ly·​fish ˈjel-ē-ˌfish How to pronounce jellyfish (audio)
: a free-swimming marine coelenterate that is the sexually reproducing form of a hydrozoan or scyphozoan and has a nearly transparent saucer-shaped body and extensible marginal tentacles studded with stinging cells

More from Merriam-Webster on jellyfish

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