sē´zar (ΚαιÌσαÏ, KaıÌsar): Originally the surname of the Julian gens (Thus, Caius Julius Caesar); afterward a name borne by the Roman emperors. In the New Testament the name is definitely applied to Augustus (, “Caesar Augustusâ€), to whom it belonged by adoption, and to Tiberius (, “Tiberius Caesarâ€; compare , ). The “Caesar†to whom Paul appealed (, , ) was Nero. The form is perpetuated in “Kaiser†and “Czar.