The Collaborative International Dictionary of English v.0.48:

Speculate \Spec"u*late\, v. i. [imp. & p. p. Speculated; p.
   pr. & vb. n. Speculating.] [L. speculatus, p. p. of
   speculari to spy out, observe, fr. specula a lookout, fr.
   specere to look. See Spy.]
   1. To consider by turning a subject in the mind, and viewing
      it in its different aspects and relations; to meditate; to
      contemplate; to theorize; as, to speculate on questions in
      religion; to speculate on political events.
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            It is remarkable that persons who speculate the most
            boldly often conform with the most pefect quietude
            to the external regulations of society. --Hawthorne.
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   2. (Philos.) To view subjects from certain premises given or
      assumed, and infer conclusions respecting them a priori.
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   3. (Com.) To purchase with the expectation of a contingent
      advance in value, and a consequent sale at a profit; --
      often, in a somewhat depreciative sense, of unsound or
      hazardous transactions; as, to speculate in coffee, in
      sugar, or in bank stock.
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