Lewis & Short

pondĕrōsus, a, um, adj. [pondus], of great weight, weighty, heavy, ponderous.

  1. I. Lit.: compedes, Plaut. Capt. 3, 5, 64: frumentum, Varr. R. R. 1, 52 fin.: verbera, Val. Max. 1, 8 fin.
    Comp.:     lana ponderosior, Varr. R. R. 2, 11; Plin. 21, 17, 67, § 107.
    Sup.: ponderosissimi lapides, Plin. 36, 19, 30, § 138.
  2. II. Trop.: ponderosa epistola, weighty, significant, Cic. Att. 2, 11, 1: vox, weighty, imposing, Val. Max. 6, 4, 1 ext.