The Collaborative International Dictionary of English v.0.48:

Struggle \Strug"gle\, n.
   1. A violent effort or efforts with contortions of the body;
      agony; distress.
      [1913 Webster]

   2. Great labor; forcible effort to obtain an object, or to
      avert an evil. --Macaulay.
      [1913 Webster]

   3. Contest; contention; strife.
      [1913 Webster]

            An honest might look upon the struggle with
            indifference.                         --Addison.
      [1913 Webster]

   Syn: Endeavor; effort; contest; labor; difficulty.
        [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Struggle \Strug"gle\, v. i. [imp. & p. p. Struggled; p. pr. &
   vb. n. Struggling.] [OE. strogelen; cf. Icel. strj?ka to
   stroke, to beat, to flog, Sw. stryka to stroke, to strike,
   Dan. stryge, G. straucheln to stumble. Cf. Stroll.]
   1. To strive, or to make efforts, with a twisting, or with
      contortions of the body.
      [1913 Webster]

   2. To use great efforts; to labor hard; to strive; to contend
      forcibly; as, to struggle to save one's life; to struggle
      with the waves; to struggle with adversity.
      [1913 Webster]

            The brave men, living and dead, who struggled here,
            have consecrated it [Gettysburg] far above our power
            to add or detract.                    --Lincoln.
      [1913 Webster]

   3. To labor in pain or anguish; to be in agony; to labor in
      any kind of difficulty or distress.
      [1913 Webster]

            'T is wisdom to beware,
            And better shun the bait than struggle in the snare.
                                                  --Dryden.
      [1913 Webster]

   Syn: To strive; contend; labor; endeavor.
        [1913 Webster]

WordNet (r) 3.0 (2006):

struggle
    n 1: an energetic attempt to achieve something; "getting through
         the crowd was a real struggle"; "he fought a battle for
         recognition" [syn: struggle, battle]
    2: an open clash between two opposing groups (or individuals);
       "the harder the conflict the more glorious the triumph"--
       Thomas Paine; "police tried to control the battle between the
       pro- and anti-abortion mobs" [syn: conflict, struggle,
       battle]
    3: strenuous effort; "the struggle to get through the crowd
       exhausted her"
    v 1: make a strenuous or labored effort; "She struggled for
         years to survive without welfare"; "He fought for breath"
         [syn: fight, struggle]
    2: to exert strenuous effort against opposition; "he struggled
       to get free from the rope"
    3: climb awkwardly, as if by scrambling [syn: clamber,
       scramble, shin, shinny, skin, struggle, sputter]
    4: be engaged in a fight; carry on a fight; "the tribesmen
       fought each other"; "Siblings are always fighting"; "Militant
       groups are contending for control of the country" [syn:
       contend, fight, struggle]

Moby Thesaurus II by Grady Ward, 1.0:

175 Moby Thesaurus words for "struggle":
   Kilkenny cats, action, aerial combat, affray, agonize, aim,
   altercation, argument, armored combat, assay, attempt, battle,
   battle royal, be determined, be hard put, beat about, bickering,
   blunder, box, brawl, broil, brush, buffet, bullfight, careen,
   career, cat-and-dog life, clash, clash of arms, close, cockfight,
   collide, combat, come to blows, compete, competition, conflict,
   contend, contention, contentiousness, contest, contestation,
   controversy, cut and thrust, debate, determination, disputation,
   dispute, dogfight, drudgery, duel, effort, embroilment, encounter,
   endeavor, enmity, essay, exchange blows, exchange of blows,
   exertion, falter, fence, feud, fight, fight a duel, fighting,
   fire fight, flounce, flounder, fray, give and take,
   give satisfaction, grapple, grapple with, ground combat,
   grunt and sweat, hand-to-hand combat, hand-to-hand fight, hassle,
   have trouble, hostility, house-to-house combat, huff and puff,
   jostle, joust, labor, labor under difficulties, litigation,
   logomachy, lurch, match, mix it up, naval combat, offer, paper war,
   passage of arms, pitch, pitch and plunge, pitched battle, plunge,
   polemic, quarrel, quarreling, quarrelsomeness, rassle, reel,
   resolution, resolve, riot, rock, roll, rumble, run a tilt,
   running fight, scramble, scrapping, scrimmage, scuffle, seek,
   seethe, shoving match, skirmish, spar, squabbling, squirm, stagger,
   stand-up fight, strain, street fight, strife, strive, striving,
   struggling, study, stumble, sway, sweat, sweat blood, swing,
   tauromachy, thrash about, thrust and parry, tilt, toil, toss,
   toss and tumble, toss and turn, totter, tourney, travail, trial,
   try, tug-of-war, tumble, tussle, twist, undertake, undertaking,
   vie, wage war, walk on eggshells, wallop, wallow, war,
   war of words, warfare, welter, wiggle, words, work, worm,
   wrangling, wrestle, wriggle, writhe