TUTOR. The KJV rendering of ἐπίτροπος, G2208, (RSV Guardian) in Galatians 4:2. The Lat. word tutor was a Rom. legal term for the guardian of a youth not legally old enough to manage his own affairs. The word has passed into Eng. with the same meaning. It is used in this sense in Eng. only in the language of law, but is otherwise obsolete. The Gr. word ἐπίτροπος, G2208, is also found in Matthew 20:8 and Luke 8:3, but in these passages it is rendered steward.

International Standard Bible Encyclopedia (1915)

tu’-ter: In modern English an "instructor," more particularly a private instructor, but the word properly means a "guardian." Hence its use in Ga 4:2 the King James Version for epitropos, here "guardian" (so the Revised Version (British and American)), and 1Co 4:15; Ga 3:24,25 the Revised Version (British and American) for paidagogos.

See Schoolmaster.