The Collaborative International Dictionary of English v.0.48:

Moisture \Mois"ture\, n. [Cf. OF. moistour, F. moiteur.]
   1. A moderate degree of wetness. --Bacon.
      [1913 Webster]

   2. That which moistens or makes damp or wet; exuding fluid;
      liquid in small quantity.
      [1913 Webster]

            All my body's moisture
            Scarce serves to quench my furnace-burning heat.
                                                  --Shak.
      [1913 Webster]

WordNet (r) 3.0 (2006):

moisture
    n 1: wetness caused by water; "drops of wet gleamed on the
         window" [syn: moisture, wet]