1)Responsibility
2)Accountability
3)Flexibility
4)Availability
Those are 4 of the things i think are required to be a professional.
As for responsibility, somebody of great amount of information available on line, from books or papers, TV shows, could be speaking a lot of somethihng in detail, but when he or she is able to take responsibility, it is hard to call professional.
Ond for the second one, accountability, one is supposed to tell things comprehensively to non-prfessional ones when required. Saying something so difficult that no one except his colleagues could understand is not 'professional'. This point is sometimes misunderstood when we grow up to be 2nd or 3rd year prfessional.
Flexibility--- very often are there exceptions, or unexcepted things when we are working. On those occasions trouble shooting is something more difficult than just doing jobs precisely or without any mistakes. Most of the things are 'context-dependent' and the definition of the professional might be that you can deal with things you have never seen in before.
And availability: one should be aware that ' i am relied uopn by those coming to my office for consultation'
no matter how trivial they are, your clients are coming to you with expectation to accept professional skills or opinions for their requests.
My frined who are working as a consultant used to tell me that one day some stupid guys came to him and demanded something redicukous from him. Hed was then pissed off. But my opinion for that is that one thinkingof their process to come for cousultation, in their other tasks, and unless it is apparent that there is a bad intention to disturb your business, maybe we should at least tell them in easy words how come it is just meaningless.
Writing those things myself just have to think of how much i am or i am not oneof those established professional.