jellyfish

noun
jel·ly·fish | \ˈje-lē-ˌfish \

Definition of jellyfish 

1a : 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

b : siphonophore

c : ctenophore

2 : a person lacking backbone or firmness

Illustration of jellyfish

Illustration of jellyfish

jellyfish 1a

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Synonyms & Antonyms for jellyfish

Synonyms

doormat, namby-pamby, pushover, weakling, wimp

Antonyms

stalwart

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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

During the day, the upside-down jellyfish Cassiopea pulses about once a second. Michael Greshko, National Geographic, "Brainless Creatures Can Do Some Incredibly Smart Things," 21 May 2018 Keep an eye out for reddish-brown lion’s mane jellyfish. Susan Moeller, BostonGlobe.com, "A beachcombing guide: Things to find at the beach," 2 May 2018 Tracking studies have shown that leatherbacks migrate from Indonesian beaches across the Pacific to feed on jellyfish in California waters. Gary Robbins, sandiegouniontribune.com, "San Diego's scientists span the globe to unearth new discoveries, solve deepest mysteries," 15 Apr. 2018 The flash sheets, taped to the front desk, featured designs by the staff at Armageddon: skulls, black cats, flaming hearts with swords piercing them, spiders, roses, jellyfish, an upside-down bat and a unicorn smoking a cigar. Zoe Greenberg, New York Times, "Friday the 13th, a ‘Tattoo Holiday’," 13 July 2018 Comb Jellies Comb jellies aren’t jellyfish, but a separate group called ctenophores which don’t have numerous tentacles or pack a sting. National Geographic, "Living Fireworks, These Animals Produce Light Shows with Their Bodies," 30 June 2018 More: Florida lifeguards treat more than 800 for jellyfish stings. Matthew Diebel, USA TODAY, "Ee-ew! Authorities warn as sea lice invade beaches in Pensacola, northwest Florida," 27 June 2018 There were enormous violet starfish, and fried egg jellyfish, big enough to fill a skillet. Matthew Kronsberg, WSJ, "An Unmissable Outdoor Adventure in Canada’s Gulf Islands," 21 June 2018 The baby jellyfish float by every year during the summer months. National Geographic, "What's Giving Some Beachgoers Rashes? Get the Facts.," 28 June 2018

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.

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First Known Use of jellyfish

1841, in the meaning defined at sense 1a

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Statistics for jellyfish

Last Updated

13 Oct 2018

Look-up Popularity

Time Traveler for jellyfish

The first known use of jellyfish was in 1841

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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·ly·fish | \ˈje-lē-ˌfish \

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·ly·fish | \ˈjel-ē-ˌfish \

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

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Comments on jellyfish

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