Hydra

noun

Hy·​dra ˈhī-drə How to pronounce Hydra (audio)
1
: a many-headed serpent or monster in Greek mythology that was slain by Hercules and each head of which when cut off was replaced by two others
2
not capitalized : a multifarious evil not to be overcome by a single effort
3
: a southern constellation of great length that lies south of Cancer, Sextans, Corvus, and Virgo and is represented on old maps by a serpent
4
not capitalized : any of numerous small tubular freshwater hydrozoan polyps (Hydra and related genera) having at one end a mouth surrounded by tentacles

Word History

Etymology

Middle English Ydra, Idre, borrowed from Latin Hydra "any of various mythical monsters, especially the Hydra of Lerna killed by Hercules, a constellation," borrowed from Greek hýdra "aquatic snake, the Hydra of Lerna, a constellation"; (sense 4) borrowed from New Latin, genus name, going back to Latin — more at otter

First Known Use

15th century, in the meaning defined at sense 1

Time Traveler
The first known use of Hydra was in the 15th century

Dictionary Entries Near Hydra

hydr-

Hydra

hydracarian

See More Nearby Entries 

Cite this Entry

“Hydra.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/Hydra. Accessed 23 Nov. 2024.

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Kids Definition

hydra

noun
hy·​dra
ˈhī-drə
: any of numerous small tube-shaped freshwater animals related to the jellyfishes and having a mouth surrounded by tentacles at one end

Medical Definition

hydra

noun
hy·​dra ˈhī-drə How to pronounce hydra (audio)
: any of numerous small tubular freshwater hydrozoan polyps (Hydra and related genera) having at one end a mouth surrounded by tentacles

Geographical Definition

Hydra

geographical name

Hy·​dra ˈhī-drə How to pronounce Hydra (audio)
variants or Modern Greek Ídhra
ˈēt͟h-rä How to pronounce Hydra (audio)
island of Greece in the southern Aegean Sea off the east coast of the Peloponnese area 20 square miles (52 square kilometers), population 2794
Hydriot
ˈhī-drē-ət How to pronounce Hydra (audio)
-drē-ˌät
noun
or Hydriote
ˈhī-drē-ˌōt How to pronounce Hydra (audio)
-ət

More from Merriam-Webster on Hydra

Britannica.com: Encyclopedia article about Hydra

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