Definition of "Professional" :

noun: an authority qualified to teach apprentices

noun: a person engaged in one of the learned professions

noun: an athlete who plays for pay

adjective: engaged in a profession or engaging in as a profession or means of livelihood

"The professional man or woman possesses distinctive qualifications."

adjective: characteristic of or befitting a profession or one engaged in a profession

"Professional conduct."

adjective: engaged in by members of a profession

"Professional occupations include medicine and the law and teaching."

adjective: of or relating to a profession

"We need professional advice."

adjective: of or relating to or suitable as a profession

"Professional organizations."