Lewis & Short

aequĭdĭci (sc. versus) [aequus-dico], verses containing corresponding words or expressions (ἀντιθέτους), as (Verg. E. 2, 18): alba ligustra cadunt, vaccinia nigra leguntur: “Albis enim nigra opposuit, ligustris autem vaccinia attribuit, et cadentibus legenda assignavit,” Diom. p. 498 P.