Classical Mythology. Often Hydra a water or marsh serpent with nine heads, each of which, if cut off, grew back as two; Hercules killed this serpent by cauterizing the necks as he cut off the heads.
any freshwater polyp of the genus Hydra and related genera, having a cylindrical body with a ring of tentacles surrounding the mouth, and usually living attached to rocks, plants, etc., but also capable of detaching and floating in the water.
a persistent or many-sided problem that presents new obstacles as soon as one aspect is solved.
(initial capital letter) the Sea Serpent, a large southern constellation extending through 90° of the sky, being the longest of all constellations.
any solitary freshwater hydroid coelenterate of the genus Hydra, in which the body is a slender polyp with tentacles around the mouth
a persistent trouble or evil
the hydra of the Irish problem
First recorded in 1325–75; from Latin hydra, from Greek hýdrā “water serpent” (replacing Middle English ydre, from Middle French, from Latin); see otter
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Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.
The Marvel universe more recently used the Nazi-like Hydra organization as a multiheaded big bad.
From New York Times • Jun. 19, 2024
The tail, however, acts like the mythological Hydra and grows two new heads, which, then, split into two separate animals.
From Science Daily • May 15, 2024
He started gathering intelligence on the Asian buyers, in an investigation called Operation Hydra.
From BBC • Aug. 15, 2023
Given the fact that the investigation was such a complex and many-headed Hydra involving so many states, I can see how the complexity of that could have led to a longer timeframe for the prosecution.
From Salon • Aug. 1, 2023
Ms. Paige appeared in the doorway, and behind her, many of the other Hydra girls peered in, all gasping.
From "The Marvellers" by Dhonielle Clayton
Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023
Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.
