water

1. H₂O; a clear, odorless, tasteless liquid, solidifying at 32°F (0°C, 0°R), and boiling at 212°F (100°C, 80°R), that is present in all animal and vegetable tissues and dissolves more substances than any other liquid. See volume. 2. Euphemism for urine. 3. A pharmacopeial preparation of a clear, saturated aqueous solution (unless otherwise specified) of volatile oils, or other aromatic or volatile substances, prepared by processes involving distillation or solution (agitation followed by filtration). SYN: aromatic w.. [A.S. waeter]

- w. of adhesion w. held by molecular attraction in contact with solid surfaces, but not forming an essential part of their constitution.

- alkaline w. a w. that contains appreciable amounts of the bicarbonates of calcium, lithium, potassium, or sodium.

- aromatic w. SYN: w. (3).

- baryta w. a saturated aqueous solution of barium hydroxide; used as an alkaline reagent.

- bitter w. a natural mineral w. containing Epsom salt.

- bound w. w. held to colloids and other substances and not removed by simple filtration.

- bromine w. a w. containing the bromides of magnesium, potassium, or sodium in therapeutic amounts.

- calcic w. a w. containing appreciable quantities of calcium salts in solution.

- carbonated w., carbonic w. w. that contains a considerable amount of carbonic acid in solution.

- carbon dioxide-free w. purified w. that has been boiled vigorously for 5 min or more.

- chalybeate w. a w. that contains salts of iron in appreciable quantities.

- chlorine w. a w. that contains the chlorides of sodium, potassium, calcium, and magnesium in varying amounts.

- w. of combustion SYN: w. of metabolism.

- w. of constitution w. held by a unit of structure as an essential part of its constitution, though not an ingredient of its molecules. See w. of crystallization.

- w. of crystallization w. of constitution that unites with certain salts and is essential to their arrangement in crystalline form; e.g., CuSO₄ 5H₂O.

- deionized w. w. purified by passing through ion-exchange columns.

- distilled w. w. purified by distillation.

- earthy w. a w. containing a large amount of mineral matter, chiefly sulfate, in solution.

- free w. w. in the body that can be removed by ultrafiltration and in which substances can be dissolved.

- gentian aniline w. gentian violet with saturated aniline w., a more effective stain than simple gentian violet.

- hard w. w. containing ions, such as Mg²⁺ and Ca²⁺, that form insoluble salts with fatty acid s so that ordinary soap will not lather in it.

- heavy w. D₂O; w. in which the hydrogen atoms are deuterium, or heavy hydrogen (²H), with physical properties that differ noticeably from those of ordinary w.; an elevated presence will cause a decrease in metabolic activity; used as a moderator in nuclear reactors because of its capacity to absorb neutrons. SYN: deuterium oxide.

- indifferent w. a mineral w. containing only a small quantity of saline matter.

- w. for injection w. purified by distillation for the preparation of products for parenteral use.

- intracellular w. SYN: intracellular fluid.

- lime w. calcium hydroxide solution; a saturated solution prepared by mixing 3 g of calcium hydroxide in a liter of purified cool w.. Undissolved calcium hydroxide is allowed to precipitate and the solution is dispensed without agitation; lime w. is a common ingredient in lotions and is used internally extensively in veterinary medicine.

- w. of metabolism the w. formed in the body by oxidation of the hydrogen of the food, the greatest amount being produced in the metabolism of fat (about 117 g per 100 g of fat). SYN: w. of combustion.

- mineral w. w. that contains appreciable amounts of certain salts, which give it therapeutic properties.

- potable w. a w. fit for drinking, being free from contamination and not containing a sufficient quantity of saline material to be regarded as a mineral w..

- purified w. w. obtained by distillation or deionization.

- saline w. a w. that contains neutral salts (chlorides, bromides, iodides, sulfates) in appreciable amounts.

- Selters w., Seltzer w. a mineral w. containing carbonates of sodium, calcium, and magnesium, and chloride of sodium. [Nieder Selters, a mineral spring in Prussia]

- soft w. w. lacking those ions, such as Mg²⁺ and Ca²⁺, that form insoluble salts with fatty acid s, so that ordinary soap will lather easily in it.

- sulfate w. a w. holding in solution appreciable quantities of the sulfates of calcium, magnesium, or sodium.

- sulfur w. a w. containing hydrogen sulfide or the metallic sulfides.

- total body w. (TBW) the sum of intracellular w. and extracellular w. (volume); about 60% of body weight.

- transcellular w. that fraction of extracellular w. in cerebrospinal, digestive, epithelial, introcular, pleural, sweat, and synovial secretions; about 1.5% of body weight.

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wa·ter 'wȯt-ər, 'wät- n

1) the liquid that descends from the clouds as rain, forms streams, lakes, and seas, and is a major constituent of all living matter and that is an odorless, tasteless, very slightly compressible liquid oxide of hydrogen H₂O which appears bluish in thick layers, freezes at 0°C (32°F) and boils at 100°C (212°F), has a maximum density at 4°C (39°F) and a high specific heat, is feebly ionized to hydrogen and hydroxyl ions, and is a poor conductor of electricity and a good solvent

2) liquid containing or resembling water: as

a ) (1) a pharmaceutical or cosmetic preparation made with water (2) a watery solution of a gaseous or readily volatile substance see AMMONIA WATER

b) a watery fluid (as tears or urine) formed or circulating in a living body

c) AMNIOTIC FLUID often used in pl. also BAG OF WATERS

water vi to form or secrete water or watery matter (as tears or saliva)

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wa·ter (wawґtər) (wahґtər) 1. a tasteless, odorless, colorless liquid, (H₂O)_n, used as the standard of specific gravity and of specific heat. It freezes at 0°C (32°F) and boils at 100°C (212°F). It is present in all organic tissues and in many other substances and is the most universal of the solvents. 2. aromatic w. 3. purified w.