(chemistry) Water in its standard form of H₂O, containing two protium hydrogen atoms, as opposed to heavy water.

(chemistry) Water containing deuterium instead of normal hydrogen (protium) (symbol D₂O); used as a moderator in nuclear reactors.

A spout connected to a socket to provide water from the main water supply.

An area of grassland, besides a river, that is subject to periodic flooding.

(uncountable) A surge of pressure in a pipe carrying a fluid; especially the banging sound in a steam or hot water pipe caused by bubbles of air, or by an abrupt alteration of the flow.

The removal of calcium and magnesium ions from water, or their replacement with sodium, either by chemical reaction or by ion exchange.

A facility, comparable to a wind tunnel, in which an underwater component may be tested in a controlled flow of water. / A tunnel used to transport water.

contamination of water, especially surface water, by sewage effluent, fertilizer runoff, industrial chemical discharge etc.

A potentially fatal medical condition, also called water intoxication, caused by extremely rapid intake of water. / Contaminating a water source with a toxin.

ocean dumping