jellyfish

Thân thiện

A child points at a jellyfish floating in the aquarium.

Definition

Noun: 1. A soft, gelatinous marine animal, typically free-swimming, with a bell-shaped or umbrella-shaped body and trailing tentacles that often bear stinging cells. Jellyfish are coelenterates (cnidarians) and represent the medusa life stage of certain species. 2. (Informal) A person perceived as weak, indecisive, or lacking in resilience or backbone.

Usage and Examples

• Noun (Marine Animal):

  • We saw a beautiful but dangerous jellyfish floating near the shore.
  • The sting from a box jellyfish can be extremely painful and even fatal.
  • The aquarium has a special exhibit featuring bioluminescent jellyfish.

• Noun (Informal, for a person):

  • Don't be such a jellyfish; you need to stand up for yourself!
  • He was called a political jellyfish for refusing to take a firm stance on the issue.

Advanced Usage and Notes

• The term "jellyfish" is scientifically imprecise, as it encompasses animals from two different classes within the phylum Cnidaria: Scyphozoa (true jellyfish) and Hydrozoa (which includes many hydromedusae). Some large siphonophores (like the Portuguese man o' war) are also commonly called jellyfish, though they are colonial organisms.
• The informal, derogatory use comparing a person to a jellyfish relies on the animal's soft, boneless, and drifting nature as a metaphor for weakness.

Variants and Related Words

• Medusa (n): The scientific term for the free-swimming, often umbrella-shaped life stage of a cnidarian, which is what is commonly called a jellyfish.
• Cnidarian (n): The phylum name for the group of animals that includes jellyfish, corals, and sea anemones.
• Nematocyst (n): The microscopic stinging cell found in the tentacles of jellyfish and other cnidarians.
• Bloom (n): A large, often dense aggregation of jellyfish, as in "a jellyfish bloom."

Synonyms

• (For the marine animal): Medusa, sea jelly (modern preferred term in some aquariums).
• (For a weak person): Weakling, pushover, milquetoast, coward.

Related Phrases and Collocations

• Jellyfish sting: The injury caused by contact with a jellyfish's tentacles.
  • She put vinegar on the jellyfish sting.
• Jellyfish bloom / swarm: A large, localized population of jellyfish.
  • A jellyfish bloom forced the beach to close.

Học thuật

Noun

1. any of numerous usually marine and free-swimming coelenterates that constitute the sexually reproductive forms of hydrozoans and scyphozoans
2. large siphonophore having a bladderlike float and stinging tentacles

Từ đồng nghĩa

• Portuguese man-of-war
• man-of-war