hydrate
    n 1: any compound that contains water of crystallization
    v 1: supply water or liquid to in order to maintain a healthy
         balance; "the bicyclists must be hydrated frequently"
    2: become hydrated and combine with water
    3: cause to be hydrated; add water or moisture to; "hydrate your
       skin" [ant: dehydrate, desiccate, dry up, exsiccate]

Hydrate \Hy"drate\, n. [Gr. "y`dwr water: cf. F. hydrate.]
   (Chem.)
   (a) A compound formed by the union of water with some other
       substance, generally forming a neutral body, as certain
       crystallized salts.
   (b) A substance which does not contain water as such, but has
       its constituents (hydrogen, oxygen, hydroxyl) so arranged
       that water may be eliminated; hence, a derivative of, or
       compound with, hydroxyl; hydroxide; as, ethyl hydrate, or
       common alcohol; calcium hydrate, or slaked lime.
       [1913 Webster]

Hydrate \Hy"drate\, v. t. [imp. & p. p. Hydrated; p. pr. & vb.
   n. Hydrating.]
   To form into a hydrate; to combine with water.
   [1913 Webster]