Emily Dickinson Lexicon

SCHOOL'MAS-TER, n. [See Master.]

1. The man who presides over and teaches a school; a teacher, instructor, or preceptor of a school. [Applied now only or chiefly to the teachers of primary schools.] Adrian VL was sometime schoolmaster to Charles V. Knolles.
2. He or that which disciplines, instructs, and leads. The law was our schoolmaster to bring us to Christ. Gal. iii.