noun

1. a person who professes something; esp., one who openly declares his sentiments, religious beliefs, etc.
2. 1. a college or university teacher of the highest academic rank; full professor
   2. assistant professor & associate professor
   3. loosely any college, university, or, occas., secondary-school teacher
3. ☆ any person claiming or assumed to be especially skilled or experienced in some art, sport, etc.: a popular or humorous usage

Etymology: ME professoure < L, teacher < professus: see profess