Lewis & Short

flexănĭmus, a, um, adj. [flecto + animus] (poet.).

  1. I. Act., that bends or sways the heart, moving, affecting: o flexanima atque omnium regina rerum oratio, Pac. ap. Non. 113, 32 (Trag. Rel. v. 177 Rib.); cf.: tantam vim habet illa, quae recte a bono poëta dicta est flexanima atque omnium regina rerum oratio, Cic. de Or. 2, 44, 187: amor, Cat. 64, 331: concentus, Mart. Cap. 9, § 906.
  2. * II. Pass., touched, moved, affected: flexanima, tamquam lymphata aut Bacchi sacris commota, Pac. ap. Cic. Div. 1, 36, 80 (Trag. Rel. v. 422 Rib.).