hydro-, hydra-, hydr-, hyd-

(Greek: water)

oscheohydrocele
Hydrocele [serous fluid] in the sac of a scrotal hernia.
oxyhydrocephalus (s) (noun), oxyhydrocephaluses (pl)
A type of hydrocephalus in which the head has a pointed shape: Jane was astonished to see a photo of a man on the internet with an oxyhydrocephalus instead of a head formed like her own.
oxyhydrogen (adjective) (not comparable)
Regarding something that consists of a mixture of oxygen and hydrogen: An oxyhydrogen blaze or flame can heat quartz rods and create or produce quartz fiber.
panhydrometer (s) (noun), panhydrometers (pl)
A water meter that can be used to measure the relative density of any liquid.
podohydrosis
The excessive sweating of the feet.
polydipsia
The drinking of water in abnormally large amounts.

It may be psycogenic, or secondary to dehydration due to any cause, or an attempt to keep up with a sustained polyuria, as in diabetes insipidus or diabetes mellitus.

proshydrotaxis
Positive galvanotaxis.
pseudohydrophobia (s) (noun) (no plural)
1. An excessive fear of what is assumed to be hydrophobia, but which may only seem to be hydrophobia: Some individuals suffering from pseudohydrophobia have an exaggerated and irrational animosity towards rabies, imagining that the disease is present, and therefore they don't drink any water, thinking that it is contaminated with rabies and can cause throat pains.
2. Any viral disease that has symptoms similar to rabies, but which is not: When Jane took her dog which showed symptoms of the infectious disease to the vet, the condition turned out to be just a pseudophydrohobia and quite harmless and easy to cure!
scaphohydrocephalus, scaphohydrocephaly
Hydrocephalus in which the head assumes a boatlike shape.
speleohydrology
The study of how water is involved in the formation of caves.
stenohydric
1. A very narrow flow of water.
2. Tolerant of a narrow range of moisture levels or humidity.
3. Having a narrow tolerance of environmental moisture that is characterized by very exacting limits: a reference to certain organisms; especially, plants.
telehydrobarometer
An instrument for recording the pressure of a head of water or other liquid.
thymohydroquinone
A substance occurring in the urine after the ingestion of thymol that colors the urine green.
zymohydrolosis (s) (noun), zymohydroloses (pl)
Fermentation or the process by which complex organic compounds are broken down: By the action of enzymes, a compound of carbon and another element is decomposed into simpler compounds without the use of oxygen.

Cross references of word families that refer to "water": aqua-; hydat-; hygro-.