The Collaborative International Dictionary of English v.0.48:

Schoolmaster \School"mas`ter\, n.
   1. The man who presides over and teaches a school; a male
      teacher of a school.
      [1913 Webster]

            Let the soldier be abroad if he will; he can do
            nothing in this age. There is another personage
            abroad, -- a person less imposing, -- in the eyes of
            some, perhaps, insignificant. The schoolmaster is
            abroad; and I trust to him, armed with his primer,
            against the soldier in full military array.
                                                  --Brougham.
      [1913 Webster]

   2. One who, or that which, disciplines and directs.
      [1913 Webster]

            The law was our schoolmaster, to bring us unto
            Christ.                               --Gal. iii.
                                                  24.
      [1913 Webster]

WordNet (r) 3.0 (2006):

schoolmaster
    n 1: presiding officer of a school [syn: headmaster,
         schoolmaster, master]
    2: any person (or institution) who acts as an educator
    3: food fish of warm Caribbean and Atlantic waters [syn:
       schoolmaster, Lutjanus apodus]

Moby Thesaurus II by Grady Ward, 1.0:

28 Moby Thesaurus words for "schoolmaster":
   abecedarian, certified teacher, docent, doctor, dominie, don,
   educationist, educator, fellow, guide, guru, instructor, maestro,
   master, melamed, mentor, mullah, pandit, pedagogist, pedagogue,
   preceptor, professor, pundit, rabbi, schoolkeeper, schoolteacher,
   starets, teacher



Easton's 1897 Bible Dictionary:

Schoolmaster
   the law so designated by Paul (Gal. 3:24, 25). As so used, the
   word does not mean teacher, but pedagogue (shortened into the
   modern page), i.e., one who was intrusted with the supervision
   of a family, taking them to and from the school, being
   responsible for their safety and manners. Hence the pedagogue
   was stern and severe in his discipline. Thus the law was a
   pedagogue to the Jews, with a view to Christ, i.e., to prepare
   for faith in Christ by producing convictions of guilt and
   helplessness. The office of the pedagogue ceased when "faith
   came", i.e., the object of that faith, the seed, which is
   Christ.


Bouvier's Law Dictionary, Revised 6th Ed (1856):

SCHOOLMASTER. One employed in teaching a school.
     2. A schoolmaster stands in loco parentis in relation to the pupils
committed to his charge, while they are under his care, so far as to enforce
obedience to his, commands, lawfully given in his capacity of school-master,
and he may therefore enforce them by moderate correction. Com. Dig. Pleader,
3 M 19; Hawk. c. 60, sect. 23. Vide Correction.
     3. The schoolmaster is justly entitled to be paid for his important and
arduous services by those who employ him. See 1 Bing. R. 357 8 Moore's Rep.
368. His duties are to teach his pupils what he has undertaken, and to have
a special care over their morals. See 1 Stark. R. 421.