The Collaborative International Dictionary of English v.0.48:

Entrepreneur \En`tre*pre*neur"\, n. [F. See Enterprise.]
   (Polit. Econ.)
   One who takes the initiative to create a product or establish
   a business for profit; generally, whoever undertakes on his
   own account an enterprise in which others are employed and
   risks are taken. --F. A. Walker.
   [1913 Webster +PJC]

WordNet (r) 3.0 (2006):

entrepreneur
    n 1: someone who organizes a business venture and assumes the
         risk for it [syn: entrepreneur, enterpriser]