mūlĭo, ōnis, m. [mulus], a mule-keeper, a mule-driver, muleteer; a mule-dealer, mule-hirer (mostly ante-class. and postAug.).
I Lit., Varr. L. L. 5, § 159 Müll.; Plaut. Most. 3, 2, 93: mulionesque cum cassidibus, Caes. B. G. 7, 45; Suet. Ner. 30; Planc. ap. Cic. Fam. 10, 18, 3; Cic. ap. Plin. 7, 43, 44, § 135; Gell. 15, 4, 3; Paul. Sent. 3, 6, 72; Juv. 3, 317.—A sobriquet applied to Vespasian, because his necessities had obliged him to make money by trading, Suet. Vesp. 4.—Prov.: infantior quam meus est mulio, Varr. ap. Non. 56, 11.—
II Transf., a kind of gnat , an enemy to bees, Plin. 11, 18, 19, § 61.