Lewis & Short

flaccĕo, ēre, v. n. [flaccus], to be flabby or flaccid.

  1. I. Lit. (post-class.): aures pendulae atque flaccentes, Lact. Opif. D. 8, 8.
  2. II. Trop., to be faint, languid, weak; to flag, droop: flaccet, languet, deficit, Non. 110, 10 (mostly ante- and post-class.): sceptra flaccent, Att. ap. Non. 110, 12: flaccet fortitudo. Afran. ib. 13: sin flaccebunt condiciones, Enn. ap. Non. 110, 14 (Trag. v. 401 ed. Vahl.): oratio vestra rebus flaccet, spiritu viget, App. Apol. p. 290: Messala flaccet, flags, loses courage, * Cic. Q. Fr. 2, 14, 4 (cf.: Messala languet, id. Att. 4, 15, 7): erunt irrigua ejus flaccentia, i. e. dried up, Vulg. Isa. 19, 10.