The most simple definition of a professional is someone who can be held personally responsible for their work. A short list would include doctors, lawyers, accountants, engineers, architects, etc. These professionals have degrees and accreditation which means they can be held accountable for their mistakes. Yes, these professionals can be sued and lose their license to work in their chosen profession.
People in sales are not professionals by definition. We are experts, a trusted advisor or an authority with experience, training and qualifications, that’s it.
This doesn’t mean that we are not accountable. Accountability for us is self imposed and our long term success depends on it.