A "professional racer" refers to someone who competes in races as their job. They get paid to participate in races instead of doing it as a hobby or for fun. Full definition
Become professional racer and set records, achieve glory and the best cars ever seen! (freepcapp.com)
At certain points in the season, a real - life professional racer must be beaten at their own event, which is usually a fairly easy task. (playstationlifestyle.net)
Woodcliff Lake, N.J. — Jan. 22, 2018... The January 26th BMW Endurance Challenge at Daytona will provide the opening act for the 56th annual Rolex 24 at Daytona weekend as privateer and professional racers from all over the world begin another season of sports car racing in North America. (press.bmwgroup.com)