The Collaborative International Dictionary of English v.0.48:

Postulate \Pos"tu*late\, v. t. [imp. & p. p. Postulated; p.
   pr. & vb. n. Postulating.]
   1. To beg, or assume without proof; as, to postulate
      conclusions.
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   2. To take without express consent; to assume.
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            The Byzantine emperors appear to have . . .
            postulated a sort of paramount supremacy over this
            nation.                               --W. Tooke.
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   3. To invite earnestly; to solicit. [Obs.] --Bp. Burnet.
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