The Collaborative International Dictionary of English v.0.48:

Refund \Re*fund"\ (r?*f?nd"), v. t. [Pref. re- + fund.]
   To fund again or anew; to replace (a fund or loan) by a new
   fund; as, to refund a railroad loan.
   [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Refund \Re*fund"\ (r?*f?nd"), v. t. [L. refundere; pref. re- re-
   + fundere to pour: cf. F. refondre, refonder. See Fuse to
   melt, and cf. Refound to cast again, 1st Refuse.]
   1. To pour back. [R. & Obs.]
      [1913 Webster]

            Were the humors of the eye tinctured with any color,
            they would refund that color upon the object. --Ray.
      [1913 Webster]

   2. To give back; to repay; to restore.
      [1913 Webster]

            A governor, that had pillaged the people, was . . .
            sentenced to refund what he had wrongfully taken.
                                                  --L'Estrange.
      [1913 Webster]

   3. To supply again with funds; to reimburse. [Obs.]
      [1913 Webster]

WordNet (r) 3.0 (2006):

refund
    n 1: money returned to a payer
    2: the act of returning money received previously [syn:
       refund, repayment]
    v 1: pay back; "Please refund me my money" [syn: refund,
         return, repay, give back]

Moby Thesaurus II by Grady Ward, 1.0:

83 Moby Thesaurus words for "refund":
   abate, abatement, agio, allow, allowance, amends, atone, atonement,
   bank discount, bate, breakage, cash discount, chain discount,
   charge off, charge-off, compensate, compensation, concession, cut,
   deduct, deduction, depreciate, depreciation, discount, drawback,
   give satisfaction, indemnification, indemnify, kick back, kickback,
   make allowance, make amends, make good, make reparation,
   make restitution, make up for, make up to, making good, pay back,
   pay damages, pay in kind, paying back, penalty, penalty clause,
   percentage, premium, price reduction, price-cut, quit, rebate,
   rebatement, recompense, recoup, recoupment, redress, reduce,
   reduction, refundment, reimburse, reimbursement, reparation, repay,
   repayment, requital, requite, restitution, retribution, return,
   rollback, salvage, satisfaction, setoff, square, squaring,
   take a premium, take off, tare, time discount, trade discount,
   tret, underselling, write off, write-off