The Collaborative International Dictionary of English v.0.48:

Relent \Re*lent"\ (r?-l?nt"), v. i. [imp. & p. p. Relented; p.
   pr. & vb. n. Relenting.] [F. ralentir, fr. L. pref. re- re-
   + ad to + lentus pliant, flexible, slow. See Lithe.]
   1. To become less rigid or hard; to yield; to dissolve; to
      melt; to deliquesce. [Obs.]
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            He stirred the coals till relente gan
            The wax again the fire.               --Chaucer.
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            [Salt of tartar] placed in a cellar will . . . begin
            to relent.                            --Boyle.
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            When opening buds salute the welcome day,
            And earth, relenting, feels the genial ray. --Pope.
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   2. To become less severe or intense; to become less hard,
      harsh, cruel, or the like; to soften in temper; to become
      more mild and tender; to feel compassion.
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            Can you . . . behold
            My sighs and tears, and will not once relent?
                                                  --Shak.
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