The Collaborative International Dictionary of English v.0.48:

Freshen \Fresh"en\, v. t. [imp. & p. p. Freshened; p. pr. &
   vb. n. Freshening]
   1. To make fresh; to separate, as water, from saline
      ingredients; to make less salty; as, to freshen water,
      fish, or flesh.
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   2. To refresh; to revive. [Obs.] --Spenser.
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   3. (Naut.) To relieve, as a rope, by change of place where
      friction wears it; or to renew, as the material used to
      prevent chafing; as, to freshen a hawse. -- Totten.
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   To freshen ballast (Naut.), to shift Or restore it.

   To freshen the hawse, to pay out a little more cable, so as
      to bring the chafe on another part.

   To freshen the way, to increase the speed of a vessel.
      --Ham. Nav. Encyc.
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