What does hydra mean?
A hydra is most famously the many-headed water serpent of Greek mythology. In that story, the Hydra of Lerna was nearly impossible to defeat because its heads regenerated when severed, and Heracles eventually had to overcome it by burning its neck after the monster was weakened. Outside mythology, “hydra” describes something with many difficult or interconnected parts, especially a problem that seems to produce additional problems whenever one is addressed. It can therefore refer metaphorically to sprawling organizations, complicated systems, or a succession of troublesome difficulties. The word is also used for a simple freshwater animal known for its remarkable regenerative abilities, and as the name of a southern constellation. Its vivid mythological history makes it especially effective in descriptions of persistent, multi-faceted challenges.
nounIn Greek mythology, a water serpent with multiple heads, whose severed heads regrew. By extension, a hydra can mean a person, creature, or problem that seems to produce further difficulties whenever one is overcome.
- A serpent in Greek mythology, especially the many-headed Hydra of Lerna, slain by Heracles as the second of his Twelve Labours.
- A person, creature, organization, or problem characterized by numerous interconnected or rapidly recurring parts.
- A small, simple freshwater animal with a tubular body and tentacles around its mouth, belonging to the cnidarian group and commonly called a hydra.
- The name of a large constellation in the southern sky, representing the mythical water serpent.
"The campaign became a hydra, with each solved problem creating a new challenge."
"Heracles defeated the Hydra of Lerna after overcoming its rapidly regenerating heads."
"The project uncovered a hydra of dependencies, each requiring separate maintenance."
"A hydra can regenerate parts of its body, although it does not grow new heads."
The usual plural for the common noun is “hydras.” In the names of astronomical constellations, the plural is also “Hydras.”
"Several hydras were identified in the wetland survey."
The Hydra of Lerna was said to regrow a head for every head cut off, making it the ancient symbol of a problem that creates more problems as it is attacked.
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Where does hydra come from?
The English word comes through Latin from Greek hydra, meaning “water snake.” The Greek hydra was a many-headed serpent associated with the marsh of Lerna, and its name is related to the Greek root for water that also underlies forms such as hydro, hydrogen, and hydraulic. In English, the word retained its mythological meaning before becoming a metaphor for a complex situation with many branching parts.
How hydra is actually used
In general use, the word is usually figurative and carries a dramatic or slightly literary tone. The mythological reference is normally understood by readers in English-speaking cultures.
Easily confused with hydra
A hydro is a hydroelectric power plant or system, whereas a hydra is a mythological many-headed serpent or a branching, difficult problem.