Lewis & Short

măgistĕrĭum, ii, n. [magister], the office of a president, chief, director, superintendent, etc. (class.).

  1. I. Lit.
    1. A. In gen.: dictaturā ac magisterio equitum honorata familia, Suet. Tib. 3: morum, i. e. the censorship, Cic. Prov. Cons. 19, 46: me magisteria delectant a majoribus instituta (sc. conviviorum), the custom of having a master or president at feasts, id. Sen. 14, 46: collegii, Suet. Dom. 4: sacerdotii, id. Calig. 22: pedestre, the office of a commander of infantry, Aur. Vict. Caes. 42.
      Transf., of dogs: inter se exercent etiam magisteria, the post of leader (in hunting), Plin. 8, 40, 61, § 148.
    2. B. In partic., the office of tutor or instructor of youth, tutorship, guardianship (very rare): jam excessit mi aetas ex magisterio tuo, I have now outgrown your tutorship, Plaut. Bacch. 1, 2, 44.
  2. II. Trop., teaching, instruction, advice: virtute id factum, et magisterio tuo, Plaut. Most. 1, 1, 32: vana, Tib. 1, 4, 84: novum, method, Cels. 5, 27, 2.