Lewis & Short

dis-sŏnus, a, um, adj., opp. consonus, dissonant, discordant, confused (not anteAug.; nor in Verg., Ov., or Hor.).

  1. I. Lit.: chorus canentium dissonum quiddam canere, Col. 12, 2, 4; so, clamores, Liv. 4, 28; Plin. Ep. 3, 20, 4: voces (opp. congruens clamor), Liv. 30, 34: questus, Tac. A. 1, 34: vapor, i. e. making a dissonant sound, Plin. 2, 43, 43, § 112.
      1. 2. In gen., disagreeing, different: gentes sermone moribusque, Liv. 1, 18; cf.: linguā agmina, Sil. 16, 19: linguis castra, id. 3, 221; linguis turba, Claud. Laud. Stil 1, 152: diversi postulantium habitus ac dissonae voces, Plin. Pan. 56, 6: ora vulgi, Luc. 3, 289: nationes, Amm. 23, 6 et saep.: venustas (opp. jucunde consonat), Quint. 9, 3, 72: cursus solis, Plin. 36, 10, 15, § 73: carmina, i. e. in elegiac measure, Stat. S. 2, 2, 114: nationes, Mart. Cap. 2, § 203: elementa, id. 9, § 912 et saep.
        With ab: nihil apud Latinos dissonum ab Romana re, Liv. 8, 8, 2.
  2. * II. Trop., discordant, jarring: collidens dissona corda Seditio, Sil. 11, 45.