Definition

1. Noun:
   • A small, tubular, solitary freshwater hydrozoan polyp: A simple aquatic animal belonging to the genus Hydra, characterized by a tubular body with tentacles surrounding its mouth.
   • A trouble that cannot be overcome by a single effort because of its many aspects or its persistent and pervasive quality: A problem or evil that is complex and regenerates, making it difficult to eradicate.
   • A long, faint constellation in the southern hemisphere near the equator stretching between Virgo and Cancer: The largest of the 88 modern constellations, named after the mythological serpent.
   • (Greek mythology) Monster with nine heads; when struck off each head was replaced by two new ones: A monstrous serpent slain by Hercules as the second of his Twelve Labors.

Examples of Usage

• Noun (Animal):
  • Under the microscope, we observed a hydra capturing a water flea with its tentacles.
  • The hydra is often studied in biology classes due to its remarkable regenerative abilities.
• Noun (Problem):
  • Corruption in the department proved to be a hydra; solving one issue only revealed several more.
  • The pandemic was a modern hydra, presenting new challenges with every attempted solution.
• Noun (Constellation):
  • The constellation Hydra is best viewed from the southern hemisphere in the spring.
• Noun (Mythology):
  • Hercules was tasked with defeating the Lernaean Hydra as one of his famous labors.

Advanced Usage

• "a hydra-headed problem": A problem with many complex, interconnected, and regenerating aspects.
  • The climate crisis is a hydra-headed problem requiring coordinated global action.

Variants and Related Words

• Hydra-headed (adjective): Having many facets or branches; difficult to control due to complexity.
  • The investigation uncovered a hydra-headed conspiracy.
• Hydrozoan (noun): The class of coelenterates to which the hydra animal belongs.

Synonyms

• Polyp (for the animal).
• Quagmire, morass, intractable problem (for the difficult situation).
• Serpent, monster (in mythology).

Related Idioms

• "Like the Hydra": Used to describe a situation where solving one part of a problem leads to the emergence of new problems.
  • Every reform seemed to create two new issues; it was like the Hydra.

Noun

1. small tubular solitary freshwater hydrozoan polyp
2. trouble that cannot be overcome by a single effort because of its many aspects or its persistent and pervasive quality
   • we may be facing a hydra that defies any easy solution
3. a long faint constellation in the southern hemisphere near the equator stretching between Virgo and Cancer
4. (Greek mythology) monster with nine heads; when struck off each head was replaced by two new ones
   • Hydra was slain by Hercules