Of, relating to, engaged in, or suitable for a profession: lawyers, doctors, and other professional people. Conforming to the standards of a profession: professional behavior. Engaging in a given activity as a source of livelihood or as a career: a professional writer. Performed by persons receiving pay: professional football. Having or showing great skill; expert: a professional repair job. A person following a profession, especially a learned profession. One who earns a living in a given or implied occupation: hired a professional to decorate the house. A skilled practitioner; an expert.