Lewis Short
(adjective) : lābĭlis, e, 1. labor, (post-class. for caducus, infirmus, debilis).
* Slipping, gliding, prone to slip or slide.
* Lit.: humus rivis operta sanguineis, gressus labiles evertebat,Amm. 31, 13, 6; Arnob. 2, 59.
* Causing to slip, slippery: limus,Amm. 27, 10, 11: humus,id. 15, 10, 5.—Hence. lābĭlĭter, adv., waveringly, Aug. Gen. ad Litt. 8. 3.
Charlton T. Lewis, Charles Short, A Latin Dictionary