The Collaborative International Dictionary of English v.0.48:

Mend \Mend\ (m[e^]nd), v. t. [imp. & p. p. Mended; p. pr. &
   vb. n. Mending.] [Abbrev. fr. amend. See Amend.]
   [1913 Webster]
   1. To repair, as anything that is torn, broken, defaced,
      decayed, or the like; to restore from partial decay,
      injury, or defacement; to patch up; to put in shape or
      order again; to re-create; as, to mend a garment or a
      machine.
      [1913 Webster]

   2. To alter for the better; to set right; to reform; hence,
      to quicken; as, to mend one's manners or pace.
      [1913 Webster]

            The best service they could do the state was to mend
            the lives of the persons who composed it. --Sir W.
                                                  Temple.
      [1913 Webster]

   3. To help, to advance, to further; to add to.
      [1913 Webster]

            Though in some lands the grass is but short, yet it
            mends garden herbs and fruit.         --Mortimer.
      [1913 Webster]

            You mend the jewel by the wearing it. --Shak.
      [1913 Webster]

   Syn: To improve; help; better; emend; amend; correct;
        rectify; reform.
        [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Mend \Mend\, v. i.
   To grow better; to advance to a better state; to become
   improved; to recover; to heal. --Shak.
   [1913 Webster +PJC]

   on the mend pred. a. recovering from an illness or injury.
      [PJC]

WordNet (r) 3.0 (2006):

mend
    n 1: sewing that repairs a worn or torn hole (especially in a
         garment); "her stockings had several mends" [syn: mend,
         patch, darn]
    2: the act of putting something in working order again [syn:
       repair, fix, fixing, fixture, mend, mending,
       reparation]
    v 1: restore by replacing a part or putting together what is
         torn or broken; "She repaired her TV set"; "Repair my shoes
         please" [syn: repair, mend, fix, bushel, doctor,
         furbish up, restore, touch on] [ant: break, bust]
    2: heal or recover; "My broken leg is mending" [syn: mend,
       heal]

Moby Thesaurus II by Grady Ward, 1.0:

142 Moby Thesaurus words for "mend":
   Great Leap Forward, acculturate, advance, advancement, ameliorate,
   amelioration, amend, amendment, ascent, better, bettering,
   betterment, boost, bring forward, civilize, cobble, come along,
   come on, commission, condition, convalesce, convalescent,
   convalescing, correct, darn, develop, do up, doctor, edify,
   educate, elevate, emend, enhance, enhancement, enlighten, enrich,
   enrichment, eugenics, euthenics, fatten, favor, fix, fix up,
   forward, foster, furtherance, gain, gain ground, get ahead,
   get along, get better, get well, go ahead, go forward, go straight,
   graduate, grow better, headway, heal, improve, improve upon,
   improvement, improving, lard, lift, look up, make an improvement,
   make headway, make progress, make strides, meliorate, melioration,
   mending, nurture, on the mend, overhaul, patch, patch up, perk up,
   pick up, pickup, preferment, progress, progression, promote,
   promotion, put in commission, put in order, put in repair,
   put in shape, put right, raise, ready, rebuild, recap, recondition,
   reconstruct, recover, recovering, recovery, rectify, recuperate,
   redress, refine upon, reform, refurbish, rehabilitate, rejuvenate,
   remedy, renew, renovate, repair, restoration, restore, retread,
   revamp, revise, revival, right, rise, service, set right,
   set to rights, sew up, shape up, show improvement, skyrocket,
   socialize, straighten out, take off, tinker, tinker up,
   transfigure, transform, upbeat, upgrade, uplift, upping, upswing,
   uptrend, upward mobility, vamp