one who guards, protects, watches over, or has the care of, some person or thing.-a treasurer; a keeper.-one who has the charge of a child or pupil and his estate; a guardian.-a private or public teacher.-an officer or member of some hall, who instructs students, and is responsible for their discipline.-an instructor of a lower rank than a professor.-to have the guardianship or care of; to teach; to instruct.-to play the tutor toward; to treat with authority or severity.