noun
hydra
HYD-ruh
noun
1
A many-headed serpent from Greek mythology that grew two new heads whenever one was cut off.
"Hercules had to burn each stump to stop the hydra from regrowing its heads."
2
A tiny freshwater animal with a tube-shaped body and tentacles around its mouth, related to jellyfish.
"Under the microscope, the hydra's tentacles waved slowly in the water."
3
A problem so tangled and persistent that solving one part of it just causes another part to appear.
"Corruption in the city turned out to be a hydra — every scandal they shut down led to two more."
How to Use Hydra
Learner’s notesIn plain EnglishEither the mythical many-headed monster, a microscopic pond animal, or (figuratively) a problem that keeps growing back no matter how you attack it.
Common pairings
a hydra of a problem
many-headed hydra
Word Forms
hydras plural, hydrae plural, hydræ plural
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Hercules had to burn each stump to stop the _____ from regrowing its heads.
Etymology
Named after the Hydra of Greek mythology, the multi-headed monster slain by Hercules; the tiny pond creature was named for its ability to regenerate in a similar way, and the figurative sense of an unstoppable, ever-multiplying problem comes from the same myth.