The Collaborative International Dictionary of English v.0.48:

Damp \Damp\, v. i. [imp. & p. p. Damped; p. pr. & vb. n.
   Damping.] [OE. dampen to choke, suffocate. See Damp, n.]
   1. To render damp; to moisten; to make humid, or moderately
      wet; to dampen; as, to damp cloth.
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   2. To put out, as fire; to depress or deject; to deaden; to
      cloud; to check or restrain, as action or vigor; to make
      dull; to weaken; to discourage. "To damp your tender
      hopes." --Akenside.
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            Usury dulls and damps all industries, improvements,
            and new inventions, wherein money would be stirring
            if it were not for this slug.         --Bacon.
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            How many a day has been damped and darkened by an
            angry word!                           --Sir J.
                                                  Lubbock.
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            The failure of his enterprise damped the spirit of
            the soldiers.                         --Macaulay.
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