noun, plural hydras, hydrae [hahy-dree], for 1–3
genitive hydrae [hahy-dree], for 4.
1. (often initial capital letter) Classical Mythology. 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.
2. 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.
3. a persistent or many-sided problem that presents new obstacles as soon as one aspect is solved.
4. (initial capital letter) Astronomy. the Sea Serpent, a large southern constellation extending through 90° of the sky, being the longest of all constellations.
See more synonyms on Thesaurus.com
Origin: 1325-75; < Latin < Greek hýdrā water serpent (replacing Middle English ydre < Middle French < L); see otter
Now YOU come up with a sentence (or fic? or graphic?) that best illustrates the word.