• related to work that needs special training or education
Chris, you're a nurse, so can I ask your professional opinion on bandaging ankles?
Both doctors have been charged with professional misconduct (= bad or unacceptable behaviour in their work).
• approving having the qualities that you connect with trained and skilled people, such as effectiveness, skill, organisation and seriousness of manner
It would look more professional if the letter was typed.
She always looks very professional in her smart suits.
You've done a very professional job stripping that floor!
• describes someone who does a job that people usually do as a hobby
She's a professional dancer/photographer.
He's a runner who's just turned professional. (= His running used to be a hobby, but now it is his job.)
• having the type of job that is respected because it involves a high level of education and training
Room for rent in shared house - would suit professional person.
a bar full of young professional types in suits