Lewis & Short

lapso, āre, v. freq. n. [id.], to slip, slide, stumble, fall.

  1. I. Lit. (poet. and in postAug. prose): (Priamum) in multo lapsantem sanguine nati, Verg. A. 2, 551: sanguine suo et lubrico paludum lapsantes (equi), Tac. A. 1, 65: lapsantibus equis, id. H. 1, 79: lapsantem gressum firmare, Sil. 3, 632; Flor. 2, 10, 3: Gyan vidi lapsare cruentae Vulnere Myrmidonis, fall, Stat. Th. 5, 223: plantis lapsantibus, Amm. 14, 2, 6.
  2. II. Trop. (post-class.): verba lapsantia, i. e. babbled forth, Gell. 1, 15, 1.