A professional is someone who has a specialised job which only very well trained people can perform, such as Doctors, lawyers, and teachers. These occupations are known as professional occupations. They may often get paid more than other people. In sport, a professional is someone who is paid to play. For example, Petra Kvitová and Tim Cahil are professional sportspeople.

The word "professional" is often used as an adjective, e.g.

• "He did a thoroughly professional job" (meaning: a very good one, even if he was not a professional).
• "His behaviour was always professional" (meaning: he behaved in a proper way, like someone of his profession should).