Roman cogn. (diminutive of rex, 'king'), found in the families of the Atilii (Atilius [I 17-23]) and Livineii (Livineius [I 1-2]) in the Republican Period; in the Imperial Period in other families as well.
Bibliography
1 Degrassi, FCIR, 265
2 Kajanto, Cognomina, 316 f.