What does "speculate" mean?

Speculate: (Philos.) To view subjects from certain premises given or assumed, and infer conclusions respecting them a priori.

Additional senses

  1. 2.(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.
  2. 3.To consider attentively; as, to speculate the nature of a thing. [R.] Sir W. Hamilton.

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