The Collaborative International Dictionary of English v.0.48:

Obtain \Ob*tain"\, v. t. [imp. & p. p. Obtained; p. pr. & vb.
   n. Obtaining.] [F. obtenir, L. obtinere; ob (see Ob-) +
   tenere to hold. See Tenable.]
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   1. To hold; to keep; to possess. [Obs.]
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            His mother, then, is mortal, but his Sire
            He who obtains the monarchy of heaven. --Milton.
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   2. To get hold of by effort; to gain possession of; to
      procure; to acquire, in any way.
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            Some pray for riches; riches they obtain. --Dryden.
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            By guileful fair words peace may be obtained.
                                                  --Shak.
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            It may be that I may obtain children by her. --Gen.
                                                  xvi. 2.
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   Syn: To attain; gain; procure; acquire; win; earn.

   Usage: See Attain. -- To Obtain, Get, Gain, Earn,
          Acquire. The idea of getting is common to all these
          terms. We may, indeed, with only a slight change of
          sense, substitute get for either of them; as, to get
          or to gain a prize; to get or to obtain an employment;
          to get or to earn a living; to get or to acquire a
          language. To gain is to get by striving; and as this
          is often a part of our good fortune, the word gain is
          peculiarly applicable to whatever comes to us
          fortuitously. Thus, we gain a victory, we gain a
          cause, we gain an advantage, etc. To earn is to
          deserve by labor or service; as, to earn good wages;
          to earn a triumph. Unfortunately, one does not always
          get or obtain what he has earned. To obtain implies
          desire for possession, and some effort directed to the
          attainment of that which is not immediately within our
          reach. Whatever we thus seek and get, we obtain,
          whether by our own exertions or those of others;
          whether by good or bad means; whether permanently, or
          only for a time. Thus, a man obtains an employment; he
          obtains an answer to a letter, etc. To acquire is more
          limited and specific. We acquire what comes to us
          gradually in the regular exercise of our abilities,
          while we obtain what comes in any way, provided we
          desire it. Thus, we acquire knowledge, property,
          honor, reputation, etc. What we acquire becomes, to a
          great extent, permanently our own; as, to acquire a
          language; to acquire habits of industry, etc.
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