Hydra

Hydra may refer to:

* Lernaean Hydra, a mythological many-headed serpent
* hydra-, an alternate spelling of the prefix hydro-, referring to water.
* The internet advertising company Hydra LLC, Hydra Network.

It may also refer to:

In science

* Hydra (constellation), the largest of the modern star constellations.
* Hydra (moon), the third moon of the Pluto.

* "Hydra" (genus), a genus of simple fresh-water animals of the class Hydrozoa.
* Hydra-Centaurus Supercluster, a supercluster of galaxies.

In technology

* Hydra (chess), a chess computer.
* Hydra (operating system).
* Hydra (software), a software used to test weak computer network passwords.
* HYDRA Game Development Kit, a retro games development system, by André LaMothe.
* HMS "Hydra", the name of several Royal Navy vessels.
* Hydra, a hydrogen ship.
* Hydra 70, an air-to-ground rocket.
* Hydra Project (EU Project), EU funded research project.
* Hydra was the original code name for Microsoft Terminal Services software.
* Lucidlogix Hydra, a load balancing chip for GPUs.

In society

* Hydra, Saronic Islands, a Greek island.
* Hydra, a city in Algeria.
* The Hydra, a literary magazine once edited by Wilfred Owen.
* , a roller coaster at Dorney Park.

In music

* Hydra Entertainment, hip hop record label.
* Hydra Head Records, an independent record label.
* "Hydra (Iris Album)" , an album by Synthpop band, Iris.
* "Hydra" (album), an album by Toto.
* Hydra (band), a Southern Rock band.
* "Hydra" (Satariel album), an album by Satariel.

In fiction

* HYDRA, a secret criminal organization in the Marvel Universe.
** …led by Viper (Madame Hydra), a Marvel supervillain, and enemy of the Avengers.
* Hydra ("Transformers"), one of several Transformers characters.
* The Hydra, a Cthulhu Mythos deity created by Henry Kuttner.
** Mother Hydra, co-ruler of the Deep One race and consort of Father Dagon in the fictional Cthulhu mythos.
* The Hydra flak tank in the "Warhammer 40,000" universe.
* Hydra, a DHARMA Initiative station on the TV series "Lost".
* Hydra. a VTOL fighter jet on the video game "".

Other

Hydra may also be used for:
* Hydra Network, a performance-based CPA advertising affiliate network.
* Hydra e.V., a German prostitutes' organization, see German Hydra e.V. Wikipedia article.