The Collaborative International Dictionary of English v.0.48:

Renew \Re*new"\ (r?-n?"), v. t. [imp. & p. p. Reneved (-n?d");
   p. pr. & vb. n. Renewing.] [Pref. re- + new. Cf.
   Renovate.]
   1. To make new again; to restore to freshness, perfection, or
      vigor; to give new life to; to rejuvenate; to
      re["e]stablish; to recreate; to rebuild.
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            In such a night
            Medea gathered the enchanted herbs
            That did renew old Aeson.             --Shak.
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   2. Specifically, to substitute for (an old obligation or
      right) a new one of the same nature; to continue in force;
      to make again; as, to renew a lease, note, or patent.
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   3. To begin again; to recommence.
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            The last great age . . . renews its finished course.
                                                  --Dryden.
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   4. To repeat; to go over again.
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            The birds-their notes renew.          --Milton.
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   5. (Theol.) To make new spiritually; to regenerate.
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            Be ye transformed by the renewing of your mind.
                                                  --Rom. xii. 2.
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WordNet (r) 3.0 (2006):

renewing
    adj 1: tending to impart new life and vigor to; "the renewing
           warmth of the sunshine" [syn: renewing, restorative,
           reviving, revitalizing, revitalising]