Lewis & Short

tectōrĭus, a, um, adj. [tego], of or belonging to covering or to a cover.

  1. I. In gen. (very rare): paniculum, thatch, Plaut. Mil. 1, 1, 18.
    Hence,
    1. B. Subst.: tectō-rĭum, ii, n., a covering, cover, Cato, R. R. 11, 2.
  2. II. In partic., that belongs to or serves for covering or overlaying walls, ceilings, floors, etc.; of or belonging to staining, painting, stuccoing, plastering, etc. (freq. and class.): opus, Varr. R. R. 1, 57, 1; cf. id. ib. 3, 11, 2: neque id (sepulcrum) opere tectorio exornari, Cic. Leg. 2, 26, 65: atramentum tectorium, that serves for staining or washing walls, Plin. 35, 6, 25, § 43: saetae e penicillis tectoriis, plasterers’ brushes, id. 28, 17, 71, § 235.
    Hence,
    1. B. Subst.: tec-tōrĭum, ii, n., plaster, stucco, fresco-painting, a wash for walls, etc.: parietes ac camarae munitae tectorio, Varr. R. R. 3, 8, 1; Cic. Div. 2, 27, 58; id. Verr. 2, 1, 55, § 145; id. Q. Fr. 3, 1, 1; id. Att. 1, 10, 3; Vitr. 7, 2, sq.; 5, 10; Sen. Ep. 86, 8; Col. 8, 15, 5; Plin. 35, 16, 56, § 194; 36, 23, 55, § 176; Dig. 15, 3, 3.
      Satirically, a paste of flour put on the face to preserve the beauty of the complexion: tandem aperit vultum et tectoria prima reponit, cover, coating, Juv. 6, 467.
      1. 2. Trop., of speech, smooth words, flattery (very rare): dignoscere cautus, Quid solidum crepet et pictae tectoria linguae, Pers. 5, 24; so imitated, Aug. Ep. 1 ad Volusian.