Lewis & Short

mollĭtūdo, ĭnis, f. [mollis], suppleness, flexibility, softness (class.).

  1. I. Lit.: mollitudo vocis, flexibility of the voice, Auct. Her. 3, 11, 20: manuum, Pac. ap. Gell. 2, 26, 13: assimilis spongiis mollitudo, Cic. N. D. 2, 55, 136: viarum, Vitr. 10, 6 init.; 10, 2, 11.
  2. II. Trop., softness, susceptibility, weakness: humanitatis, Cic. de Or. 3, 40, 161: corrumpi mollitudine vitiorum, Arn. 2, 64.