Lewis & Short

explĭcābĭlis, e, adj. [explico], that may be explained, explicable (very rare): mensura, Plin. 4, 13, 28, § 98.
Adv.: ex-plĭcābĭlĭter, in an explicable manner, acc. to Diom. p. 401 P.; Mar. Plot. de Metr. p. 2623.