hydration

1. Chemically, the addition of water; differentiated from hydrolysis, where the union with water is accompanied by a splitting of the original molecule and the water molecule. SEE ALSO: solvation. 2. Clinically, the taking in of water; used commonly in the sense of reduced h. or dehydration. 3. The formation of a shell of water molecules around a molecular entity.

- absolute h. actual water excess as measured by a difference from the normal or from a given water content.

* * *

hy·dra·tion hī-'drā-shən n

1) the act or process of combining or treating with water: as

a) the introduction of additional fluid into the body <\hydration sometimes helps to reduce the concentration of toxic substances in the tissues>

b) a chemical reaction in which water takes part with the formation of only one product <\hydration of ethylene to ethyl alcohol> esp a reaction in which water takes part in the form of intact molecules

2) the quality or state of being hydrated esp the condition of having adequate fluid in the body tissues

* * *

hy·dra·tion (hi-draґshən) 1. the act of combining or causing to combine with water. 2. the condition of being combined with water.