Hydra
- Antifragile (EP)
- Camp X
- Dawn of the Dragonstar
- Deep One
- Dharma Initiative
- Ghidra
- Greek destroyer Hydra
- Greek frigate Hydra
- Greek ironclad Hydra
- Greek ship Hydra
- HMS Hydra
- HMS Hydra (1797)
- HMS Hydra (1838)
- HMS Hydra (1871)
- HMS Hydra (1912)
- HMS Hydra (A144)
- HMS Hydra (J275)
- HYDRA Game Development Kit
- Habang Nilalamon ng Hydra ang Kasaysayan
- Henry Kuttner deities
- Hydra (Chuck)
- Hydra (Marvel Cinematic Universe)
- Hydra (Otep album)
- Hydra (Toto album)
- Hydra (Transformers)
- Hydra (Within Temptation album)
- Hydra (association)
- Hydra (band)
- Hydra (chess)
- Hydra (comics)
- Hydra (constellation)
- Hydra (digital repository)
- Hydra (film)
- Hydra (genus)
- Hydra (island)
- Hydra (moon)
- Hydra (operating system)
- Hydra (ship)
- Hydra (skater)
- Hydra (software)
- Hydra (video game)
- Hydra (wrestler)
- Hydra 100
- Hydra 70
- Hydra Entertainment
- Hydra Market
- Hydra Technologies
- Hydra Trophy
- Hydra game
- Hydra the Revenge
- Hydra, Algeria
- Hydra-class minelayer
- Hydra-class sloop
- Hydro (disambiguation)
- Hydrus
- Iris (American band)
- Kirby Air Ride
- L'Hydre anarchiste
- Lernaean Hydra
- Macabre (album)
- Main (band)
- NEC HYDRAstor
- Operation Hydra (1943)
- Operation Hydra (Yugoslavia)
- Overview of RESTful API Description Languages
- Prototype 2
- Razer Hydra
- Satariel (band)
- Stigmata (Arch Enemy album)
- The Hydra
- The Phantom
- The Thrillseekers
- UFO Ultramaiden Valkyrie