jellyfish

noun jel·ly·fish \ ˈje-lē-ˌfish \
Updated on: 10 Nov 2017

Definition of jellyfish

1 a : 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
2 : a person lacking backbone or firmness

Examples of jellyfish in a Sentence

  1. a jellyfish who was afraid to tell her boss that her latest brainstorm was just plain bad

Recent Examples of jellyfish from the Web

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.

Illustration of jellyfish

First Known Use of jellyfish

1841

jellyfish Synonyms

Synonyms
doormat, weakling, namby-pamby, pushover, reed, wimp
Antonyms
stalwart
Related Words
coward, milquetoast, mouse, nebbish, nervous Nellie (or nervous Nelly), pussy [slang], wuss (also wussy); sheep
Near Antonyms
mensch

JELLYFISH Defined for English Language Learners

jellyfish

noun

Definition of jellyfish for English Language Learners

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


JELLYFISH Defined for Kids

jellyfish

noun jel·ly·fish \ ˈje-lē-ˌfish \

Definition of jellyfish for Students

: 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

Medical Dictionary

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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