Hydra

noun
Hy·​dra | \ ˈhī-drə How to pronounce Hydra (audio) \

Definition of Hydra

 (Entry 1 of 2)

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

Hydra

geographical name
Hy·​dra | \ ˈhī-drə How to pronounce Hydra (audio) \
variants: or Modern Greek Ídhra \ ˈēt͟h-​rä How to pronounce Hydra (audio) \

Definition of Hydra (Entry 2 of 2)

island of Greece in the southern Aegean Sea off the east coast of the Peloponnese area 20 square miles (52 square kilometers), population 2794

Other Words from Hydra

Geographical name

Hydriot \ ˈhī-​drē-​ət How to pronounce Hydra (audio) , -​drē-​ˌät \ or Hydriote \ ˈhī-​drē-​ˌōt How to pronounce Hydra (audio) , -​ət \ noun

First Known Use of Hydra

Noun

15th century, in the meaning defined at sense 1

History and Etymology for Hydra

Noun

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

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Time Traveler for Hydra

Time Traveler

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

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Cite this Entry

“Hydra.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/Hydra. Accessed 2 Mar. 2021.

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More Definitions for Hydra

hydra

noun
hy·​dra | \ ˈhī-drə How to pronounce hydra (audio) \

Medical Definition of hydra

: any of numerous small tubular freshwater hydrozoan polyps (Hydra and related genera) having at one end a mouth surrounded by tentacles

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