(chemistry) Water with a low concentration of dissolved minerals, especially calcium, making it easier to lather with soap.

(chemistry) Water with a high concentration of dissolved minerals, especially calcium, making it difficult to lather with soap.

Any of various aquatic insects of the family Corixidae that have paddle-shaped hind legs used for swimming.

Any of various freshwater aquatic beetles that have a smooth oval body and flattened hind legs adapted for swimming, and that carry an air bubble underneath their abdomens.

Having a great depth of water. / Carried out at great depth. / Located in or near deep ocean waters. / Living at a great depth underwater

Carbonated water, water that has carbon dioxide dissolved in it and has been stored under pressure in a bottle. Usually mixed before drinking with another beverage.

Used other than figuratively or idiomatically: see deep, water. / Waters suitable for deep-draft ships, especially ocean-going. / (idiomatic) A difficult or embarrassing situation.

The highest quality of gemstones, especially of diamonds and pearls. / (by extension) The highest rank or quality or the greatest degree.

(US) Any of various aquatic or semi-aquatic rodents from Florida and southern Georgia, especially Neofiber alleni; the muskrat. / (Australia) A water mouse, especially, the rakali, Hydromys chrysogaster.

Water with a very low content of dissolved salt, as opposed to brackish water or salt water.