The Collaborative International Dictionary of English v.0.48:

Attain \At*tain"\ ([a^]t*t[=a]n"), v. t. [imp. & p. p.
   Attained (-t[=a]nd"); p. pr. & vb. n. Attaining.] [Of.
   atteinen, atteignen, atainen, OF. ateindre, ataindre, F.
   atteindre, fr. L. attingere; ad + tangere to touch, reach.
   See Tangent, and cf. Attinge, Attaint.]
   1. To achieve or accomplish, that is, to reach by efforts; to
      gain; to compass; as, to attain rest.
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            Is he wise who hopes to attain the end without the
            means?                                --Abp.
                                                  Tillotson.
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   2. To gain or obtain possession of; to acquire. [Obs. with a
      material object.] --Chaucer.
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   3. To get at the knowledge of; to ascertain. [Obs.]
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            Not well attaining his meaning.       --Fuller.
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   4. To reach or come to, by progression or motion; to arrive
      at. "Canaan he now attains." --Milton.
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   5. To overtake. [Obs.] --Bacon.
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   6. To reach in excellence or degree; to equal.
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   Syn: To Attain, Obtain, Procure.

   Usage: Attain always implies an effort toward an object.
          Hence it is not synonymous with obtain and procure,
          which do not necessarily imply such effort or motion.
          We procure or obtain a thing by purchase or loan, and
          we obtain by inheritance, but we do not attain it by
          such means.
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The Collaborative International Dictionary of English v.0.48:

Attain \At*tain"\, n.
   Attainment. [Obs.]
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The Collaborative International Dictionary of English v.0.48:

Attain \At*tain"\, v. i.
   1. To come or arrive, by motion, growth, bodily exertion, or
      efforts toward a place, object, state, etc.; to reach.
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            If by any means they might attain to Phenice. --Acts
                                                  xxvii. 12.
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            Nor nearer might the dogs attain.     --Sir W.
                                                  Scott.
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            To see your trees attain to the dignity of timber.
                                                  --Cowper.
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            Few boroughs had as yet attained to power such as
            this.                                 --J. R. Green.
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   2. To come or arrive, by an effort of mind.
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            Such knowledge is too wonderful for me; it is high,
            I can not attain unto it.             --Ps. cxxxix.
                                                  6.
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WordNet (r) 3.0 (2006):

attain
    v 1: to gain with effort; "she achieved her goal despite
         setbacks" [syn: achieve, accomplish, attain, reach]
    2: reach a point in time, or a certain state or level; "The
       thermometer hit 100 degrees"; "This car can reach a speed of
       140 miles per hour" [syn: reach, hit, attain]
    3: find unexpectedly; "the archeologists chanced upon an old
       tomb"; "she struck a goldmine"; "The hikers finally struck
       the main path to the lake" [syn: fall upon, strike, come
       upon, light upon, chance upon, come across, chance
       on, happen upon, attain, discover]
    4: reach a destination, either real or abstract; "We hit Detroit
       by noon"; "The water reached the doorstep"; "We barely made
       it to the finish line"; "I have to hit the MAC machine before
       the weekend starts" [syn: reach, make, attain, hit,
       arrive at, gain]

Moby Thesaurus II by Grady Ward, 1.0:

70 Moby Thesaurus words for "attain":
   accede, accomplish, achieve, approach, arrive, arrive at,
   arrive in, attain to, be instated, be received, blow in, bob up,
   check in, clock in, come, come in, come to, come to hand, compass,
   consummate, deal with, discharge, dispatch, dispose of, do,
   do the job, do the trick, effect, effectuate, enact, execute,
   fetch, fetch up at, find, fulfill, gain, get in, get there, get to,
   hit, hit town, knock off, make, make good, make it, manage,
   mount the throne, perform, polish off, pop up, produce, pull in,
   punch in, put away, reach, realize, ring in, roll in, score,
   show up, sign in, succeed, take care of, take office, time in,
   turn the trick, turn up, win, work, work out