noun
full professor
The highest academic rank at a university, above associate professor (准教授) and lecturer/assistant professor.
彼は今年、正教授に昇進した。
He was promoted to full professor this year.
Can refer to any professor rank, but often implies full professor in context.
Compound of 正 (sei, 'full' or 'regular') and 教授 (kyōju, 'professor'). The prefix 正 distinguishes the full rank from other professorial titles.