The Collaborative International Dictionary of English v.0.48:

Baffle \Baf"fle\, v. i.
   1. To practice deceit. [Obs.] --Barrow.
      [1913 Webster]

   2. To struggle against in vain; as, a ship baffles with the
      winds. [R.]
      [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Baffle \Baf"fle\, n.
   1. A defeat by artifice, shifts, and turns; discomfiture.
      [R.] "A baffle to philosophy." --South.
      [1913 Webster]

   2. (Engin.)
      (a) A deflector, as a plate or wall, so arranged across a
          furnace or boiler flue as to mingle the hot gases and
          deflect them against the substance to be heated.
      (b) A grating or plate across a channel or pipe conveying
          water, gas, or the like, by which the flow is rendered
          more uniform in different parts of the cross section
          of the stream; -- used in measuring the rate of flow,
          as by means of a weir.
          [Webster 1913 Suppl.]

   2. (Coal Mining) A lever for operating the throttle valve of
      a winding engine. [Local, U. S.]
      [Webster 1913 Suppl.]

The Collaborative International Dictionary of English v.0.48:

Baffle \Baf"fle\ (b[a^]f"f'l), v. t. [imp. & p. p. Baffled
   (-f'ld); p. pr. & vb. n. Baffling (-fl[i^]ng).] [Cf.
   Lowland Scotch bauchle to treat contemptuously, bauch
   tasteless, abashed, jaded, Icel. b[=a]gr uneasy, poor, or
   b[=a]gr, n., struggle, b[ae]gja to push, treat harshly, OF.
   beffler, beffer, to mock, deceive, dial. G. b[aum]ppe mouth,
   beffen to bark, chide.]
   [1913 Webster]
   1. To cause to undergo a disgraceful punishment, as a
      recreant knight. [Obs.]
      [1913 Webster]

            He by the heels him hung upon a tree,
            And baffled so, that all which passed by
            The picture of his punishment might see. --Spenser.
      [1913 Webster]

   2. To check by shifts and turns; to elude; to foil.
      [1913 Webster]

            The art that baffles time's tyrannic claim.
                                                  --Cowper.
      [1913 Webster]

   3. To check by perplexing; to disconcert, frustrate, or
      defeat; to thwart. "A baffled purpose." --De Quincey.
      [1913 Webster]

            A suitable scripture ready to repel and baffle them
            all.                                  --South.
      [1913 Webster]

            Calculations so difficult as to have baffled, until
            within a . . . recent period, the most enlightened
            nations.                              --Prescott.
      [1913 Webster]

            The mere intricacy of a question should not baffle
            us.                                   --Locke.
      [1913 Webster]

   Baffling wind (Naut.), one that frequently shifts from one
      point to another.
      [1913 Webster]

   Syn: To balk; thwart; foil; frustrate; defeat.
        [1913 Webster]

WordNet (r) 3.0 (2006):

baffle
    n 1: a flat plate that controls or directs the flow of fluid or
         energy [syn: baffle, baffle board]
    v 1: be a mystery or bewildering to; "This beats me!"; "Got me--
         I don't know the answer!"; "a vexing problem"; "This
         question really stuck me" [syn: perplex, vex, stick,
         get, puzzle, mystify, baffle, beat, pose,
         bewilder, flummox, stupefy, nonplus, gravel,
         amaze, dumbfound]
    2: hinder or prevent (the efforts, plans, or desires) of; "What
       ultimately frustrated every challenger was Ruth's amazing
       September surge"; "foil your opponent" [syn: thwart,
       queer, spoil, scotch, foil, cross, frustrate,
       baffle, bilk]
    3: check the emission of (sound) [syn: baffle, regulate]

Moby Thesaurus II by Grady Ward, 1.0:

131 Moby Thesaurus words for "baffle":
   addle, amaze, babble, bafflement, balk, ball up, bamboozle,
   be Greek to, be beyond one, be too deep, beat, beat one, befuddle,
   bewilderment, bilk, blast, boggle, bother, brave, buffalo,
   cast down, challenge, checkmate, circumvent, confound,
   confoundment, confront, confuse, confusion, contravene, counter,
   counteract, countermand, counterwork, cross, cushion, damp, dampen,
   dash, daze, deaden, deafen, defeat, defeat expectation, defy,
   destroy, dilemma, disappoint, discomfit, discomposure, disconcert,
   disconcertedness, disconcertion, disconcertment, discountenance,
   dish, disillusion, disrupt, dissatisfy, disturbance, dull,
   dumbfound, elude, embarrass, embarrassment, enigma, escape one,
   faze, fix, floor, flummox, fog, foil, frustrate, fuddle, get,
   gibber, jam, keep in suspense, knock the chocks, let down, lick,
   lose one, maze, mix up, muddle, muffle, mute, mystery, mystify,
   need explanation, nonplus, not make sense, not penetrate,
   pass comprehension, perplex, perplexity, perturbation, pickle,
   plight, pother, predicament, problem, puzzle, puzzlement, quandary,
   rattle, riddle, ruin, sabotage, scotch, scrape, soft-pedal, soften,
   speak in tongues, spike, spoil, stew, stick, stonewall, stop,
   stump, subdue, talk double Dutch, tantalize, tease, throw, thwart,
   tone down, unassuredness, upset