One who professed, or makes open declaration of, his sentiments or opinions; especially, one who makes a public avowal of his belief in the Scriptures and his faith in Christ, and thus unites himself to the visible church.

One who professed, or publicly teaches, any science or branch of learning; especially, an officer in a university, college, or other seminary, whose business it is to read lectures, or instruct students, in a particular branch of learning; as a professor of theology, of botany, of mathematics, or of political economy.