A professional athlete.
Professional player of that sport. Only 1% of people in sports gets to be on a professional team.
Someone who plays the violin is a violinist.
You call someone who plays any instrument alone a "soloist."
someone who plays the sport of lacrosse
Someone who plays the piano is called a pianist, but someone who plays the keyboard can be called a keyboardist.
A Sportsman but it some people say it by the sport they do for example If someone played football you may call them a football player If someone was in the olypmics you may call them an athlete ect
Professional Sportsman (or should that be Sportsperson?).