Someone who visits a brothel.
A prostitute
A person who belongs to a profession
A reputation known by name
An expert
One of four categories of sociologist propounded by Horowitz: a sociologist who is actively concerned with promoting the profession of sociology.
A person who earns their living from a specified activity
Expert.
Of, pertaining to, or in accordance with the (usually high) standards of a profession.
That is carried out for money, especially as a livelihood.