There is an unfortunate number of definitions; some of the better ones are:

An Entrepreneur is “[a] person who sets up a business or businesses, taking on financial risks in the hope of profit.”
(oxforddictionaries.com 2018).

An Entrepreneur is “[s]omeone who solves people’s problems at a profit.”
(The 1-Page Marketing Plan, Allan Dib).

The best definition, defined as being fit-for-purpose and having the least ambiguity and fewest contradictions is:

“Entrepreneurship is the creation of new organisations.”
(“Who Is an Entrepreneur?” Is the Wrong Question, William B. Gartner).
It follows therefore, that an Entrepreneur is a person who creates new organisations.