Speculator /(spĕk"ū̇*lā`tẽr)/

Spec·u·la·tor

Speculator

n.
  1. One who speculates. Specifically: (a) An observer; a contemplator; hence, a spy; a watcher. [Obs.]
  2. One who forms theories; a theorist.
    A speculator who had dared to affirm that the human soul is by nature mortal.
  3. One who engages in speculation; one who buys and sells goods, land, etc., with the expectation of deriving profit from fluctuations in price. (Com.)