Lewis & Short

Aesōpĭcus, a, um, adj. [Aesopus], Æsopic. Acc. to Isid. Orig. 1, 39, fables are either Æsopic or Libystic (from Libys, a writer of fables, mentioned by Hesych.); Æsopic, when brute beasts or things inanimate are represented as discoursing together; Libystic. when the discourse is between men and brutes.