- hydroElectrical power supply; specifically, electrical power provided by a utility (as a publicly-owned one); payment or bills for this.
- hydrateA solid compound containing or linked to water molecules.
- hydrangeaAny of several shrubs, of the genus Hydrangea, having large clusters of white, pink or blue flowers.
- anhydrousHaving little or no water.
- hydropsThe abnormal accumulation of serous fluid in a tissue or cavity.
- aerohydrousComposed of or containing air and water.
- hydatoidwatery, aqueous
- hydatophyteAn obligate waterplant; a plant which lives partly or completely submerged in water, such as water lettuce (Pistia stratiotes).
- hydatoscopyDivination by interpreting rainwater. Omens are drawn from the various formations and sizes of rain puddles, and bowls of rainwater are gazed upon until clairvoyant visions appear on the surface of the water, or in the mind's eye. This is considered in some cases to be more important than hydromancy because rain has fallen from the heavens, making it sacred.
- hydrohetaeroliteA tetragonal-ditetragonal dipyramidal mineral containing hydrogen, manganese, oxygen, and zinc.
- hydromelMead, especially one of low alcohol content.
- hydrophylliumOne of the flat, leaf-like, protective zooids covering other zooids of certain Siphonophorae.