Lewis & Short

2. lĭbrārĭus, a, um, adj. [3. liber],

  1. I. of or belonging to books: scriba librarius, a copyist, transcriber of books, Varr. R. R. 3, 2, 14; Cic. Agr. 2, 13, 32: libraria taberna, a bookseller’s shop, Cic. Phil. 2, 9, 21: scriptor, a transcriber of books, Hor. A. P. 354: atramentum, ink for writing books, Plin. 27, 7, 28, § 52.
    Hence,
  2. II. Subst.
    1. A. lĭ-brārĭus, i, m.
      1. 1. A transcriber of books, a copyist, scribe, secretary, Cic. Agr. 2, 5, 13: librum ut tuis librariis daret, id. Att. 12, 40, 1: librarii mendum, Liv. 38, 55, 8: legionis, the secretary of the legion, Inscr. ap. Grut. 365, 1; cf. Sen. Contr. 1, 7, 18; Juv. 9, 109.
      2. 2. A bookseller, Sen. Ben. 7, 6, 1; Gell. 5, 4, 2; 18, 4, 1; Sulp. Sev. Dial. 1, 23, 4.
      3. 3. (Sc. doctor.) An elementary teacher, Hier. Ep. 107, 4.
    2. B. lĭbrārĭa, ae, f.
      1. 1. A female scribe: (Parcae) utpote librariae Superum archivumque custodes, Mart. Cap. 1, § 65 (perh. also Juv. 6, 476; cf. sub 1. librarius).
      2. 2. A bookseller’s shop; in libraria, ego et Julius Paulus poëta consederamus, Gell. 5, 4, 1: quispiam in libraria sedens, id. 13, 30, 1.
    3. C. lĭbrārĭum, ii, n., a place to keep books in, a bookcase, bookchest: exhibe librarium illud legum vestrarum, Cic. Mil. 12, 33: libraria omnia exurerent, Amm. 29, 2, 4.