The Collaborative International Dictionary of English v.0.48:

Conspire \Con*spire"\ (k[o^]n*sp[imac]r"), v. i. [imp. & p. p.
   Conspired (k[o^]n*sp[imac]rd"); p. pr. & vb. n.
   Conspiring.] [F. conspirer, L. conspirare to blow together,
   harmonize, agree, plot; con- + spirare to breathe, blow. See
   Spirit.]
   1. To make an agreement, esp. a secret agreement, to do some
      act, as to commit treason or a crime, or to do some
      unlawful deed; to plot together.
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            They conspired against [Joseph] to slay him. --Gen.
                                                  xxxvii. 18.
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            You have conspired against our royal person,
            Joined with an enemy proclaimed.      --Shak.
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   2. To concur to one end; to agree.
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            The press, the pulpit, and the stage
            Conspire to censure and expose our age. --Roscommon.

   Syn: To unite; concur; complot; confederate; league.
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