1 jellyfish | Definition of jellyfish

jellyfish

noun
jel路​ly路​fish | \ 藞je-l膿-藢fish How to pronounce jellyfish (audio) \

Definition of jellyfish

1a : : 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

Keep scrolling for more

Synonyms & Antonyms for jellyfish

Synonyms

doormat, namby-pamby, pushover, reed, weakling, wimp

Antonyms

stalwart

Visit the Thesaurus for More 

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

There are jellyfish, birds, an octopus, otters, seals and a host of special exhibits. Scott Mcmurren, Anchorage Daily News, "Everyone鈥檚 got their go-to Seattle spots. Here are a few more.," 24 Aug. 2019 The room features raw Thai silk, tons of plants, lamps resembling jellyfish, and reclaimed wood from old Thai houses and boats. Janelle Bitker, SFChronicle.com, "Kin Khao sister restaurant Nari opens in San Francisco with seasonal Thai fare," 8 Aug. 2019 At Maritime Aquarium at Norwalk, kids can see real, grown sharks in a 110,000-gallon habitat, as well as rays, otters, seals, jellyfish, octopi, sea turtles, eels, lobsters, crabs, starfish and other creatures that live in and around the ocean. Susan Dunne, courant.com, "Sharks! on exhibit through summer at the Bruce," 3 July 2019 Inside Arizona Mills is an aquarium with 30 displays and more than 5,000 ocean creatures, including clown fish, sea turtles, sharks, jellyfish, rays, octopus and seahorses. Arizona Republic, azcentral, "Summer in Arizona: Locals share 100 fun ways to survive the 100-degree heat in Phoenix," 1 July 2019 During another dive, a large jellyfish ran into my face in relatively deep depth. Georgia Frances King, Quartz, "The world鈥檚 most famous explorers on how they handle high-stress situations," 14 Aug. 2019 This is completely different from other bioluminescent ocean creatures like jellyfish and coral. Ashley Strickland, CNN, "These sharks glow bright green in the dark," 8 Aug. 2019 Now, Shaner and his team have identified five fluorescent proteins in the body of the jellyfish previously unknown to science. Eva Frederick, Science | AAAS, "This jellyfish makes glowing proteins previously unknown to science," 19 July 2019 To celebrate 20 years of jellyfish hunting and Krabby Patties, the athleisure brand teamed up with pro basketball player Kyrie Irving to specially create the Kyrie x SpongeBob SquarePants collection inspired by the show's two main characters. Kelsey Stiegman, Seventeen, "Nike Is Releasing a SpongeBob SquarePants Sneaker Collection and the Nostalgia is SO Real," 19 July 2019

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'jellyfish.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

See More

First Known Use of jellyfish

1818, in the meaning defined at sense 1a

Keep scrolling for more

Keep scrolling for more

More Definitions for jellyfish

jellyfish

noun

English Language Learners Definition of jellyfish

: a sea animal that has a very soft body and that can sting

jellyfish

noun
jel路​ly路​fish | \ 藞je-l膿-藢fish How to pronounce jellyfish (audio) \

Kids Definition of jellyfish

: a free-swimming sea animal related to the corals that has a nearly transparent jellylike body shaped like a saucer and tentacles with stinging cells

jellyfish

noun
jel路​ly路​fish | \ 藞jel-膿-藢fish How to pronounce jellyfish (audio) \

Medical Definition of jellyfish

: 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

Keep scrolling for more

More from Merriam-Webster on jellyfish

Rhyming Dictionary: Words that rhyme with jellyfish

Thesaurus: All synonyms and antonyms for jellyfish

Spanish Central: Translation of jellyfish

Nglish: Translation of jellyfish for Spanish Speakers

Britannica.com: Encyclopedia article about jellyfish