A professional is a worker required to possess a large body of
knowledge derived from extensive academic study (usually tertiary),
with the training almost always formalized. Professionals are at least
to a degree self-regulating, in that they control the training and
evaluation processes that admit new persons to the field, and in
judging whether the work done by their members is up to standard. This
differs from other kinds of work where regulation (if considered
necessary) is imposed by the state, or where official quality
standards are often lacking. Professions have some historical links to
guilds in these regards.

Professionals usually have autonomy in the workplace—they are expected
to utilize their independent judgement and professional ethics in
carrying out their responsibilities.[4] This holds true even if they
are employees instead of working on their own. Typically a
professional provides a service (in exchange for payment or salary),
in accordance with established protocols for licensing, ethics,
procedures, standards of service and training / certification.

On Mon, 28 Jul 2008 23:11:19 -0700, turtoni wrote:

who makes enough money to live.

Other criteria ...

"a 'true' professional must be proficient in all criteria for the field
of work they are practising professionally in."

are devised by academics who are in the profession of devising stuff up
until a point of absolute meaningless exists.

A typical method towards this end:

Which is academia-speak for "Here are some things off the top of my head
which will look really good on the page formatted as bullet points. The
dean loves bullet points!"