The Collaborative International Dictionary of English v.0.48:

Moisten \Mois"ten\, v. t. [imp. & p. p. Moistened; p. pr. &
   vb. n. Moistening.]
   1. To make damp; to wet in a small degree.
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            A pipe a little moistened on the inside. --Bacon.
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   2. To soften by making moist; to make tender.
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            It moistened not his executioner's heart with any
            pity.                                 --Fuller.
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