Dictionary:
pro·fes·sion·al (prə-fĕsh'ə-nəl)
adj.
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.
n.
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.
Thesaurus
professional
adjective
Having or demonstrating a high degree of knowledge or skill: adept, crack, expert, master, masterful, masterly, proficient, skilled, skillful. Slang crackerjack. See ability/inability.