(c. 400-320 B.C.), Greek grammarian of Amphipolis in Macedonia. According to Vitruvius (vii., preface) he lived during the age of Ptolemy Philadelphus (285-247 B.C.), by whom he was crucified as the punishment of his criticisms on the king. This account, however, should probably be rejected. Zoilus appears to have been at one time a follower of Isocrates, but subsequently a pupil of Polycrates, whom he heard at Athens, where he was a teacher of rhetoric. Zoilus was chiefly known for the acerbity of his attacks on Homer (which gained him the name of Homeromastix, "scourge of Homer"), chiefly directed against the fabulous element in the Homeric poems. Zoilus also wrote against Isocrates and Plato, who had attacked the style of Lysias of which he approved. The name Zoilus came to be generally used of a spiteful and malignant critic.
See U. Friedlander, De Zoilo aliisque Homeri Obtrectatoribus (Konigsberg, 1895); J. E. Sandys, History of Classical Scholarship (2nd ed. 1906).