Lewis & Short

Zōĭlus, i, m., = Ζώιλος, a severe critic in the time of Ptolemaeus Philadelphus, a censurer of Homer (hence called Ὁμηρομάστιξ, Homeromastix), Vitr. 7 praef.
Transf., of a censorious person, Ov. R. Am. 366; Mart. 11, 37, 1.