The Collaborative International Dictionary of English v.0.48:

Strive \Strive\, n.
   1. An effort; a striving. [R.] --Chapman.
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   2. Strife; contention. [Obs.] --Wyclif (luke xxi. 9).
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The Collaborative International Dictionary of English v.0.48:

Strive \Strive\, v. i. [imp. Strove; p. p. Striven(Rarely,
   Strove); p. pr. & vb. n. Striving.] [OF. estriver; of
   Teutonic origin, and akin to G. streben, D. streven, Dan.
   straebe, Sw. str[aum]fva. Cf. Strife.]
   1. To make efforts; to use exertions; to endeavor with
      earnestness; to labor hard.
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            Was for this his ambition strove
            To equal Caesar first, and after, Jove? --Cowley.
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   2. To struggle in opposition; to be in contention or dispute;
      to contend; to contest; -- followed by against or with
      before the person or thing opposed; as, strive against
      temptation; strive for the truth. --Chaucer.
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            My Spirit shall not always strive with man. --Gen.
                                                  vi. 3.
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            Why dost thou strive against him?     --Job xxxiii.
                                                  13.
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            Now private pity strove with public hate,
            Reason with rage, and eloquence with fate. --Denham.
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   3. To vie; to compete; to be a rival. --Chaucer.
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            [Not] that sweet grove
            Of Daphne, by Orontes and the inspired
            Castalian spring, might with this paradise
            Of Eden strive.                       --Milton.
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   Syn: To contend; vie; struggle; endeavor; aim.
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WordNet (r) 3.0 (2006):

strive
    v 1: attempt by employing effort; "we endeavor to make our
         customers happy" [syn: endeavor, endeavour, strive]
    2: to exert much effort or energy; "straining our ears to hear"
       [syn: strive, reach, strain]

Moby Thesaurus II by Grady Ward, 1.0:

83 Moby Thesaurus words for "strive":
   agonize, aim, aim to, assay, attempt, attempt to, battle,
   be determined, box, brawl, broil, buffet, clash, close, collide,
   combat, come to blows, compete, contend, contest, cut and thrust,
   dare to, drive, duel, endeavor, essay, exchange blows, fence, feud,
   fight, fight a duel, give and take, give satisfaction, go all out,
   grapple, grapple with, grunt and sweat, hassle, huff and puff,
   jostle, joust, labor, make every effort, mix it up, moil, offer,
   pretend to, quarrel, rassle, resolve, riot, run a tilt, scramble,
   scuffle, seek, seek to, skirmish, spar, strain, strive to,
   struggle, study, study to, sweat, sweat blood, thrust and parry,
   tilt, toil, tourney, travail, try, try and, try hard, try to, tug,
   tussle, undertake, venture to, wage war, war, work, work at,
   wrestle