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.
It is remarkable that persons who speculate the most
boldly often conform with the most pefect quietude
to the external regulations of society. --Hawthorne.
2. (Philos.) To view subjects from certain premises given or
assumed, and infer conclusions respecting them a priori.
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.