[1] : The Collaborative International Dictionary of English v.0.48

confirm \confirm"\, v. t. imp.  p. p. confrmed; p. pr. 
   vb. n. confirming. oe. confermen, confirmen, of.
   confermer, f. confirmer, fr. l. confirmare; con- + firmare to
   make firm, fr. firmus firm. see firm.
   1. to make firm or firmer; to add strength to; to establish;
      as, health is confirmed by exercise.
      1913 webster

            confirm the crown to me and to mine heirs. --shak.
      1913 webster

            and confirmed the same unto jacob for a law. --ps.
                                                  cv. 10.
      1913 webster

   2. to strengthen in judgment or purpose.
      1913 webster

            confirmed, then, i resolve
            adam shall share with me in bliss or woe. --milton.
      1913 webster

   3. to give new assurance of the truth of; to render certain;
      to verify; to corroborate; as, to confirm a rumor.
      1913 webster

            your eyes shall witness and confirm my tale. --pope.
      1913 webster

            these likelihoods confirm her flight. --shak.
      1913 webster

   4. to render valid by formal assent; to complete by a
      necessary sanction; to ratify; as, to confirm the
      appoinment of an official; the senate confirms a treaty.
      1913 webster

            that treaty so prejudicial ought to have been
            remitted rather than confimed.        --swift.
      1913 webster

   5. eccl. to administer the rite of confirmation to. see
      confirmation, 3.
      1913 webster

            those which are thus confirmed are thereby supposed
            to be fit for admission to the sacrament. --hammond.

   syn: to strengthen; corroborate; substantiate; establish;
        fix; ratify; settle; verify; assure.
        1913 webster
see also:
confrmed confirming firm confirmation 

[2] : WordNet (r) 2.0

confirm
     v 1: establish or strengthen as with new evidence or facts; "his
          story confirmed my doubts"; "the evidence supports the
          defendant" syn: corroborate, sustain, substantiate,
           support, affirm ant: negate
     2: strengthen or make more firm; "the witnesses confirmed the
        victim's account" syn: reassert
     3: make more firm; "confirm thy soul in self-control"
     4: as of a person to a position; "the senate confirmed the
        president's candidate for secretary of defense"
     5: administer the rite of confirmation to; "the children were
        confirmed in their mother's faith"
see also:
corroborate sustain substantiate support affirm negate 
reassert 

[3] : Moby Thesaurus II by Grady Ward, 1.0

204 moby thesaurus words for "confirm":
   ok, accede, accept, acclimate, acclimatize, accommodate, accredit,
   accustom, acquiesce, adapt, addict, adjust,
   administer the eucharist, affirm, amen, anoint, approve, assay,
   assent, assure, attest, audit, authenticate, authorize, autograph,
   back, back up, be sponsor for, bear out, bed, beef up, bind,
   bolster, bond, brace, brace up, break, break in, bring to test,
   buttress, case harden, certify, check, check and doublecheck,
   check out, check over, chrism, circumstantiate, clinch, collate,
   condition, consent, corroborate, cosign, countersecure,
   countersign, cross-check, cut and try, deep-dye, define, do duty,
   document, domesticate, domesticize, double-check, embed, encourage,
   endorse, engraft, engrave, ensure, entrench, essay, establish,
   etch, experiment, familiarize, fix, fortify, found, gentle, gird,
   give a try, give a tryout, give permission, give the go-ahead,
   give the imprimatur, give thumbs up, ground, guarantee, guaranty,
   habituate, harden, have a go, housebreak, impact, implant, impose,
   impress, imprint, infix, ingrain, initial, inscribe, insure, inure,
   invigorate, jam, justify, lay hands on, lodge, make good, minister,
   naturalize, nerve, notarize, officiate, orient, orientate, pack,
   painstakingly match, pass, pass on, pass upon, perform a rite,
   perform service, permit, plant, play around with, practice upon,
   print, probate, prop, prove, put to trial, ratify, recheck,
   recognize, refresh, reinforce, reinvigorate, research,
   restrengthen, road-test, root, rubber stamp, run a sample, sample,
   sanction, say amen to, scrutinize comparatively, seal, season,
   seat, second, secure, set, set in, settle, shake down, shore up,
   sign, sign and seal, sign for, sponsor, stamp, stand behind,
   stand up for, steel, stereotype, stiffen, strengthen, subscribe,
   subscribe to, substantiate, support, sustain, swear and affirm,
   swear to, take to, tame, taste, temper, test, toughen, train,
   triple-check, try, try it on, try out, undergird, underpin,
   undersign, underwrite, uphold, validate, verify, visa, vise, vouch,
   warrant, wedge, witness, wont

Confirm >> C Words
Confirm, definition of term: Confirm
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